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Automotive Abbreviations
/MIN Per minute, usually RPM, physical unit
°C Degrees Celsius, physical unit
°DK Degrees throttle-valve angle, physical unit
°F Degrees Fahrenheit, physical unit
°KW Degrees crankshaft, physical unit
°NW Degrees camshaft, physical unit
1/CM3 1/cm³, per cubic centimeter, unit
1L Axle 1 (usually front axle), left side
1R Axle 1 (usually front axle), right side
2L Axle 2, left side
2R Axle 2, right side
2WD 2-wheel drive
3L Axle 3, left side
3R Axle 3, right side
4WAS Four wheel anti skid, traction control system for four-wheel drive vehicles, refer also to ASR
4WD 4-wheel drive
4WS Four-wheel steering. All 4 wheels are steered, not just the front wheels.
4X4 Vehicle with 4 wheels, all of which are driven (all-wheel drive). See also 4WD.
A Ampere, physical unit, or Austria
A/D Analog/digital, usually A/D converter: converts analog signals (such as speed or oxygen sensor voltage) to digital signals that can be processed by a computer
A1 Axle 1, usually front axle
A2/3 Axles 2/3, rear axle(s)
AA Automatically triggered alarm
AAC Auxiliary-air control valve
AAP Acceleration auxiliary pump
AAS Drive-off assistant
AAV Activated charcoal filter shutoff valve
AB Airbag, usually proper name
ABC Active body control, chassis, see also ADS
ABD Automatic braking differential, usually proper name
ABE General operating licence, model approval of car for operation on public roads
ABS Anti-Blocking System, usually proper name
ABS 2 Anti-Blocking System separate, system name, proper name
ABS 3 Anti-Blocking System integrated in brake booster, system name, proper name
ABV Auxiliary-air valve or Automatic blocking prevention, another term for ABS
AC Air conditioning, air conditioner, or Alternating current
ACC Adaptive cruise control
Active centre differential, automatic limited-slip differential (Mitsubishi)
Airbag Control Module
Air charge temperature. Temperature of charge air with turbocharger.
ADA Atmospheric-pressure dependent full-load stop with distributor injection pumps
ADAM Advanced dynamic aid mechanism, mechanical braking assistant (Teves). See also BAS.
ADAPT Adaptation, adaption
ADB Automatic differential brake. BMW system replacing conventional limited-slip differentials (ensures traction by braking wheels). Subfunction of DSC (BMW ESP).
ADF Atmospheric pressure sensor
ADN Yemen
ADR Automatic distance control, proper name (VW), or Trigger duration control
ADS Automatic throttle-valve actuator or Active driving system or Adaptive damping system
AEI Advance electronic ignition, fully electronic ignition system
AEU Outside Europe
AFB Atmospheric-pressure dependent start-of-delivery
AFI Air-supported fuel injection
AFS Advanced front-lighting system. Variable light distribution via movable reflectors
AG Automatic transmission
AGN Exhaust-gas aftertreatment
AGR Exhaust-gas recirculation
AGRV Exhaust-gas recirculation valve
Trailer coupling, or Active rear-axle kinematics
Auxilliary Heater Module
AHS Alcohol sensor
AHV Trailer brake valve
AI Air injection
AICC Autonomous intelligent cruise control (speed and distance)
AIV Air injection valve
AK Automatic clutch. Clutch operates when driving off, shifting, and stopping.
AKEK Automatic child-seat detection, usually integrated into an airbag system
AKF Activated charcoal filter
AKS Automatic clutch system. Clutch engagement/disengagement is automatic. The clutch pedal is no longer needed. Used for example in Renault Twingo; see also EKS, or Active headrest system (BMW)
AKSE Automatic child-seat detection
AKT Active, or Current
ALB Automatic load-dependent braking force control
ALC Adaptive light control. The headlight illumination is distributed variably according to the driving situation (city, country, motorway). (BMW)
ALDA Absolute measurement, boost-pressure dependent full-load stop
ALDL Assembly Line Diagnostic Link, Opel diagnostic plug
ALFB Atmospheric pressure and load-dependent start-of-delivery
ALG Axle load sensor
ALR Automatic longitudinal control
ALU Arithmetic and logic unit (microcomputer), proper name
ALV Axle load distribution (drive-off aid)
ALWR Automatic headlight vertical aim control
AM Central America
AMIC Automotive Multimedia Interface Collaboration, Gremium zur Entwicklung eines Multimediastandards, besteht im wesentlichen aus führenden Automobilherstellern
AMR Drive torque control
ANC Active noise control. System actively influences the intake noise, reducing it by about 15 dB.
Logical AND operator
Automatic Ocupant Sensing
AP Air pump
APB Active parking brake. Teves system containing interface to electronics, with driver-assistance functions such as drive-off assistance, parking aid, and immobilizer.
APS Autopilot system
ARA Anti-jerking control
ARD Active jerking suppression
ARF Exhaust-gas recirculation
ARFR Exhaust-gas recirculation rate
ARMADA Triggering unit for restraint systems with external differentiated triggering. Airbag system from DaimlerChrysler.
ARMIN Trigger unit for restraint systems with integrated emergency-call control
ARR Exhaust-gas recirculation control
ART Distance-based cruise control
AS Air intake or Towing protection or South America
ASC Automatic stability control, controlled force transmission
ASC+T Automatic stability control, regulated force transmission with traction control
ASD Automatic limited-slip differential, usually proper name
ASF Audi Space Frame, special construction for aluminium frame in Audi A2 and A8
ASG Attachment control unit or Semi-automatic transmission
Asynchronous machine
Alarm Siren Module
ASMS Automatic stability management system. See also ESP.
AS-NO Exhaust-gas sensor for NOx (nitrogen oxide) content
ASP Shutoff valve for ASR brake control
ASR Transmission slip control, usually proper name
ASR 2 Transmission slip control, separate, system name, proper name
ASR 3 Transmission slip control, integrated, system name, proper name
AS-T Exhaust-gas sensor for temperature
ASV Air switching valve, air intake valve or Trailer control valve
AT Automatic transmission
ATB Exhaust-gas temperature limitation
ATF Exhaust-gas temperature sensor or Automatic transmission fluid
ATG Replacement transmission
ATL Exhaust-gas turbocharger
ATWS Anti-theft warning system (Opel)
AU Exhaust-gas inspection
Ultrasonic Alarm System
AUT Automatic transmission
AV Outlet valve or Shutoff valve
AW Drive shaft
AWG Evaluation switching unit
AWK Spare piston, used if proper piston does not function
AWN ASA Workshop Network, proper name
AWR Distance warning radar
AWS Evaluation switching unit (Bosch KH)
AY Lateral acceleration. A=acceleration, Y=lateral direction
AYC Active yaw control. Rear-axle limited-slip differential (Mitsubishi). See also ACD.
AZG Adaptive cylinder equalisation. Quantity equalisation control.
B Internal combustion engine (petrol) or Bank or Belgium
B- Battery negative voltage
B.C.D.D. Vacuum controlled idle air correction
B.P.T. Pressure control valve
B+ Battery positive voltage
BA Acceleration sensor or Brake assistant (Mercedes Benz)
BAR bar, physical unit
BAS Brake assistant system
BBA Service brake system. Enables the driver to reduce the speed of a vehicle in steps during operation (including to standstill). In addition to the service brake system, a vehicle can have a parking brake, a retarder system, or an auxiliary braking system. A service brake system can be a single- or multiple-circuit system and can work mechanically, hydraulically, or pneumatically.
Wideband noise test, method for testing potentiometers
Body Bus
BBV Service-brake valve. Component of service brake system. See also BBA.
BC Blink code
BCM Body control module (Opel and GM)
BD Bd: baud. Unit for data transmission rate. 1 baud is 1 bit/second.
BDE Petrol direct injection
BDM Petrol/diesel speed measurement module
BEA Bosch Emissions Analysis, product name for exhaust-gas tester (Bosch)
BEV Battery electric vehicle
BF Passenger, or passenger-side
BFA Passenger airbag. See also BF-AB.
BF-AB Passenger airbag
BFL Brake fluid level
BFS Passenger side
BG Brake assembly, integrated ABS, or Bulgaria
BHKZ Battery high voltage capacitor ignition
BIP Start pulse
BKL Brake indicator light
BKR Braking force control
BKU Braking force support
BKV Power brakes
BLDC Brushless direct current motor
BLS Brake light switch
BLU Brake light suppression. Activated when the brake assistant carries out a "preliminary charge". The main brake cylinder is actuated, leading to actuation of the light switch. Since the driver has not braked, switch-on of the brake light must be suppressed
BM Reference mark
BMR Braking torque control
BOU Brake operating unit, controls and activates the brakes
BPA Start of paraffin precipitation. Also called cloud point. Temperature at which paraffin crystals precipitate out of diesel fuel.
BPS Brake test stand
BR Brake control for ASR or Brazil
BRP Wideband noise test, method for testing potentiometers
BS Brake disc or Acceleration sensor
BSA Brake system analysis, product name for brake test stand (Bosch)
BSU Special brake inspection
BT Brake drum
BTC Bosch traffic controller, traffic monitoring system
BTS Battery disconnect switch (Mercedes)
BV Brake valve
BVA Brake wear indicator
BVSV Bimetallic-controlled vacuum switching valve or Bimetallic vacuum switching valve
BWN Bosch Workshop Network, proper name
BZ Brake cylinder
BZM Reference mark
BZW respectively, or, and/or
C Capacitor, capacitance, or Chassis (OBD error codes, for example) or Cuba
C.R. Compression ratio
C3/B7 C3/B7 signal (speed signal for trip recorder)
CAA Clean Air Act (US exhaust-gas regulations)
CAL California
Controller Area Network, mini-network for exchanging data between computers, proper name
Can Diagnostic Interface
CAN-H CAN High. One of the two data lines in the CAN bus system. See also CAN.
CAN-HI CAN High. One of the two data lines in the CAN bus system. See also CAN.
CAN-L CAN Low. One of the two data lines in the CAN bus system. See also CAN.
CAN-LO CAN Low. One of the two data lines in the CAN bus system. See also CAN.
CARB California Air Resources Board (US air-pollution authority), proper name
CARIN Autopilot system, Mercedes
Computer aided service, proper name
Collision Avoidance
CAT Catalytic converter
CB Vacuum control of starting mixture
CBC Cornering brake control
Cruise control. See also ACC
CCM really ccm or cm³, cubic centimeters, unit of volume
CCW Counter clockwise, e.g. for indicating direction of rotation of engine
Compact disc
Compact Disc Changer Rear
CDI Common Rail direct injection (in Mercedes and MCC)
CDL Central door locking, central locking system limited to doors (Opel)
CDN Canada
CELIS Central lighting system (Hella)
CEM Centralised Electronic Module (Volvo)


Cylinder-individual injection system, proper name
Cold filter plugging point (for diesels)
CGI Stratified charge gasoline injection, petrol direct injection with stratified charge through throttle valve and with compressor charging (Mercedes)
CH Hydrocarbon (normally HC). In conjunction with exhaust-gas systems, HC is understood to be the portion of unburned fuel in the exhaust, or Switzerland (Confoederatio Helvetica)
CH4 Methane, main component of natural gas (90%), compressed as fuel for natural-gas-powered cars. See also CNG
CI Ivory Coast
Camshaft identification (position) sensor
Colour Info Display
Cylinder-individual fuel injection, usually proper name
Column Intergration Module
CIN Calibration identification number. Part of OBD, consists of 3 letters and at most 12 digits. Can indicate hardware level, for example.
CKP Crankshaft positioning sensor
CMH Mixture preheating
CMP Camshaft positioning sensor
CNG Compressed natural gas, fuel for vehicles with gas-powered engines
CNS Combustion noise sensor, measures combustion noises (knock sensor)
CO Carbon monoxide. Poisonous gas present in exhaust gas. Produced during combustion of carbon with insufficient oxygen, or Colombia
CO2 Carbon dioxide, non-poisonous gas produced during combustion, also known as greenhouse gas
COMAND Cockpit management and data systems. System for data exchange and driver information management.
CPS Camshaft position/speed sensor / Crankshaft position sensor
CPU Central processing unit (microprocessor)
CPV Constant pressure valve
CPX CPx: high-pressure pump of a Common Rail diesel system, such as CP2. It is used in commercial vehicles.
CR Common Rail. See CRS.
CRC Cyclic redundancy check. Method for generating a checksum, proper name
CRI Common Rail injector. Injector of a Common Rail system, comparable to the injection valve of a conventional injection system.
CRIN Car radio identification number
CRP Common Rail pump. Special high-pressure pump for the Common Rail system, or Car phone (Opel)
CRS Common Rail system. Special diesel direct-injection system in which the fuel is distributed to the injectors via a common line (Common Rail) under high pressure.
CRT Master computer or Continuous catalytic converter regeneration by burn off at 300°C with after-injection
CRW Common Rail parameters (also CR-W)
CS Crankshaft
CSCV RPM control valve
CTG CAN tester (Mercedes)
CTS Cooling temperature sensor, Kühlmittel-Temperatursensor
CTX Continuously variable transaxle
CV Check valve, shutoff valve, throttling non-return valve
CVN Calibration verification number. Part of OBD, contains the checksums for parameter settings, for example.
CVT Continuously variable transmission
CW Drag coefficient, characteristic value for aerodynamics or drag, determines drag together with frontal area of vehicle or clockwise, e.g. for indicating direction of rotation of engine
CZ Czech Republic
D Diesel engine or Decimal number or Drive (position of automatic-transmission selector lever) or Germany
D3 German exhaust-gas standard, parallel to European standard. Corresponds largely to EU3. See EU3 and EURO3.
D4 German exhaust-gas standard, parallel to European standard. Corresponds largely to EU4. See EU4 and EURO4.
DA Boost pressure dependent full-load stop
DAB Digital audio broadcasting
DBC Dynamic brake control
DBE Roof operating unit, control unit in Mercedes, usually proper name
DBG Flow limiter
DBR Retarder (sustained action brake) or Retarder relay
DBV Pressure limiting valve
DC Direct current or DaimlerChrysler
DCU Diesel control unit or Dosing control unit. Unit for injection of urea (serves to reduce NOx).
DD Fuel pressure limiter
DDA Digital directional antenna, special antenna which blocks out radio wave reflection interference
DDE Digital Diesel Electronics, system name, usually proper name, or Direct data exchange

Engine speed versus alternator residual ripple or driver door module (Opel)

Drivers Door Module
DDS Diesel theft protection
DECT Digital enhanced cordless telecommunications, standard for data transmission, usually proper name
DEE Digital engine electronics
DF RPM sensor, or Pressure sensor, or Direct-fire, distributorless coil ignition with double ignition coil
DFA Speed sensor output
DFB Flow limiter (Common Rail) or Dynamic start-of-delivery setting
DFC Deceleration fuel control
DFHL Speed sensor, left rear
DFHR Speed sensor, right rear
DFM Dynamo field monitor. Output for recording dynamo field
DFS Double-spark coil, supplies two cylinders
DFVL Speed sensor, left front
DFVR Speed sensor, right front
DG Speed sensor, or Speed sensor for transmission input speed
DGI Direct gasoline injection
DHK Nozzle holder combination
DI Direct (diesel) injection, system name, usually proper name
DI/DIST Distributor type
DIA Diagnosis
DIAGK Diagnosis K line, communication line
DIAGL Diagnosis L line, signalling line
DIGI Digiplex (Marelli)
DIGIJET Digitally controlled fuel injection, system name, proper name
DIGIPLEX Fully electronic ignition system, system name, proper name
DIGNITION Electronic ignition system, system name, proper name
DIN German Industrial Standard
DIO Data input/output. Interface for exchanging data in both directions.
DIS Direct ignition system, proper name
DISA Differential intake manifold system (switchable, variable-length intake manifold)
DK Throttle valve or Denmark
DKA Throttle valve actuator, Ecotronic
DKE Throttle valve incrementation bit
DKG Throttle valve sensor, detects current position of throttle
DKI Throttle valve actual value. Current throttle-valve voltage
DKP Throttle valve potentiometer
DKR Throttle valve reduction or Throttle valve reduction bit
DKS Throttle valve switch
DKV Throttle valve preset
DLB Compressed-air brake
DLC Data link connector. Diagnosis connection
DLI Distributorless ignition
DLK Dynamic steering correction
DLOC Device location, Einbaulage einer Komponente
DLS Digital idle stabilisation
DLWR Dynamic headlight vertical aim control
DM dm: decimeter DM: Diagnosis module
DM3/H dm³/H: cubic decimeters per stroke, unit
DME Digital Motor Electronics (Motronic), system name, proper name
DMM Digital multimeter
DMS Elongation measurement sensor
DMV Diesel solenoid valve
DOHC Double overhead camshaft, usually part of engine designation
DP Dashpot, or Throttle valve closing damper
DPF Diesel particle filter
DPFE Delta pressure feedback electronic system or Differential pressure feedback, EGR
DPHI dphi, delta phi, difference angle. See also PHI.
DQ dQ: delta quantity, difference quantity. See also Q.
DR Pressure regulator
DRM Pressure regulator module
DRS Rotation rate sensor, sensor for vehicle dynamics control
DRV Pressure regulator valve
DS Pressure switch or Pressure sensor
DSA Dynamic stability assistance
DSB Pressure sensor in/for combustion chamber
DSC Dynamic stability control
DSE Thermal-expansion material element, expands or contracts when heated
RPM target value sensor
Drivers Seat Module
DSP Display, or Dynamic shift program (automatic transmission), or Digital sound package (VW audio equipment variant), or Digital sound processor, special processor for digital processing of audio signals
DSS Pressure-jump switch
DSTC Dynamic stability and traction control
DSU Pressure sensor for ambient pressure
DSV Pressure control valve
DTC Diagnostic trouble code
DTI Diesel direct-injection with distributor pump (Opel)
DTR Distronic. Distance control system (Mercedes)
DV Pressure supply, or Throttle device
DVD Digital versatile disc. Storage medium with significantly higher storage capacity than a conventional CD.
DVH Pressure valve holder
DWA Theft warning system, BMW-specific designation
DWS Rotation angle sensor
DYN Dynamic
DZ Breakthrough ignition or Algeria
DZG RPM sensor
DZV Digital ignition, fully electronic
E Electrical fan, or Fuel-injection engine, or Economy (shifting program for automatic transmissions), or Spain (España)
EA Original equipment
EAG Electronic automatic transmission
EAI Electronic advanced ignition, electronic ignition-curve control, ELZ
EAK Kenya
EAS Electronically autonomous starting system or electronic actuation system, usually trade name or electronic air suspension (VAG)
EAV Element shutoff valve. Shuts off an individual element of the high-pressure pump in the Common Rail system.
EBC Electronic brake force control (see EBD and EBV)
EBCV Electrical auxiliary air control valve
EBD Electronic braking differential or Electronic brake force distribution (see also EBC and EBV)
EBM Electronic brake management system. Optimises driving stability, traction, and braking function (BMW)
EBS Electronic braking system
EBV Electronic brake force distribution (see also EBD and EBC)
EC Ecuador
ECABS Electronic air cushioning, combined with ABS
ECC Electronic climate control, electronically controlled air conditioner (Opel)
ECD Electronically controlled deceleration
ECE Economic Commission of Europe, proper name
ECI Electronically Controlled Injection, system name, usually proper name
ECM Electronic Control Module, system name, usually proper name
ECO Ecotronic, system name, usually proper name
ECON ECOn: Electronic carburetor, n=version, usually proper name
ECONZ ECOnZ: Electronic carburetor and electronic ignition, n=version number, usually proper name
ECT Engine coolant temperature, or temperature sensor
ECU Electronic control unit, proper name
EDC Electronic diesel control, usually proper name
EDG Electronic diesel control with integrated transmission control. MCC control unit, proper name.
EDIS Electronic documentation and information system (Bosch)
EDIS 4 EEC IV with distributorless ignition system (Ford)
EDR Electronic diesel control NFZ-DB
EDS Electronic differential lock, usually proper name
EDW Electronic anti-theft warning system or Electronic pressure transducer
EEC Fully electronic engine control or Electronic ignition timing, proper name
EEC IV Electronic engine control system IV (Ford), system name, proper name
EECS Fuel vapour emission control system
EEM Electrical energy management. Higher-order system that coordinates the interaction of the generator, battery, voltage converter, drive train, and loads. See also EES and VSC.
EEPROM Electrically erasable programmable read-only memory, proper name
EES Electrically unlocked starting quantity, or Electrical energy systems (onboard network of the future (42V generator for electromagnetic valves, for example, 14V DCDC converter for rest of network)
EFI Electronic fuel injection, usually proper name
EFP Electronic accelerator pedal, proper name
EFS Single-spark coil, supplying one cylinder
EGAS Electronic accelerator pedal, proper name (electronic throttle control, ETC)
EGD Electronically regulated shock absorption
EGE Electronic air dryer unit
EGN EGn: EGAS control unit, n=version, usually proper name
EGO Exhaust Gas Oxygen Sensor, unbeheizte Lambdasonde
EGR Exhaust gas recirculation
EGS Electronic transmission control
EHA Electronic automatic heater, usually proper name
EHAB Electrohydraulic shutoff
EHB Electrohydraulic brake
EHCM Electrohydraulic control module
EHPS Electrohydraulic power steering
EHR Electrohydraulic lifting control

Electrohydraulic control module

Entertainment Head Unit
EHSW Electrohydraulic positioner
EI Electronic ignition
EKE Electronic fuel injection, proper name
EKM Electronic clutch management
EKP Electric fuel pump
EKRG Simple short-circuit ring sensor
EKS Electronic clutch system. Clutch engagement and disengagement is automatic. The clutch pedal is no longer needed. See also AKS.
ELAB Electrical idle shutoff valve
ELB Electronically controlled brake
ELD Electrical load-peak damping
ELF Electronic air cushioning
ELFI Electronic vehicle identification. Component of VW ELSA service information system.
ELR Electrical ignition system with ignition curve adjustment or Electronic idle control
ELRA Electronic automatic restraint. Automatic seat belts (VW)
ELS Electronic idle stabilisation
ELSA Electronic service information system. VW system for authorised workshops (garages). Comprises the components ELFI, ELWIS, and ETKA.
ELV Electrical air valve, or Electronic steering or steering-column lock. See also ESL.
EL-V Electronically controlled carburetor
ELWIS Electronic shop information system. Component of the VW ELSA service information system.
ELZ Electronic ignition
EMAB Shutoff by electromotor
EMB Electromechanical brake
EMC Electromagnetic compatibility (see also EMV)
EMF Electromechanical parking brake.
EMI Injection volume indicator
EML Electronic engine performance control, proper name
EMR Electronic volume reduction
EMS Electronic engine control, proper name
EMSE Electromagnetic start enable
EMV Electromagnetic compatibility (EMC)
ENG Engine type (code letters), or Engine
ENG FAIL Engine failures, diagnosis line for outputting errors
ENR Electronic level control
EOBD European on-board diagnosis, internal vehicle diagnosis with external tester conforming to European guidelines. Serves primarily to record exhaust-gas related faults. Usually trade name
EOL End of line, usually in conjunction with end-of-line programming
EP Adjustment point
EPA Environmental Protection Agency, air purity monitoring organisation
EPAS Electric power-assisted steering

Electropneumatic brake

Electronic Park Brake
EPC Electronic power control or Electronic pedal control (such as with ME-Motronic systems without mechanical throttle cable)
EPI Exhaust Port Injection, Nacheinspritzung in Auslasskanal (Toyota)
EPK Electropneumatic kit
EPROM Erasable programmable read-only memory, programmable or erasable with UV light, proper name
EPS Extended park position, or Injection pump test bench, sometimes used as a product identification (such as EPS 944)
EPSV Electrical injection adjustment
EPT Electronic pressure transmission
EPW Electro-pneumatic transducer, serves to transform electrical signals into pneumatic signals such as in boost-pressure regulation
ER Energy reserve
ERE Electronic inline injection system (special engine control) or Electrical regulator
ERW Energy reserve with voltage converter
ERWIN Electronic repair and workshop information. VW electronic service information system for independent workshops (garages) and fleet operators. Information offering is restricted compared to ELSA.
ES Electronic control unit or El Salvador
ESA Emissions system analysis, product name for exhaust-gas tester (Bosch) or Electronic spark advance
ESA/IZA Map ignition, ignition coil in distributor
ESC Escape key on PC or Map ignition or Electronic spark control, electronic ignition control up to knock region, with knock sensor
ESG Single-pane safety glass or Electronic switching unit for trailer detection (used in brake systems)
ESGN ESGn: Special equipment, e.g., NWS, ETS, KGE, n=version no.
ESL Electronic steering lock. See also ELV.
ESP Electronic stability program, another designation for vehicle-dynamics control (FDR), usually proper name
ESPV Electrical injection adjustment
ESR Electronic slip reduction, another name for ASR, or Electrical sunroof, electrically operated sunroof (or lifting roof)
ESS Electronic suspension systems. Continental Teves electronic air cushioning system. The system adapts automatically to vehicle load conditions, has continuously variable damping, and works together with ESP.
ESSD Electrical steel sunroof
EST Electronic spark timing, electronic map ignition control. See also MSTS
ESV Feed valve or Injection valve
ET Egypt
ETC Electronic throttle control, usually proper name or Electronic traction control
ETKA Electronic parts catalogue. Component of the VW ELSA service information system.
ETM Electronic transmission management, usually proper name
ETS Electronic thermostat control, usually proper name or Electronic traction system, see ETC
ETV Electronic throttle valve
EU European Union
EU3 European exhaust-gas standard, valid from 2000 (levels: HC 0.2, CO 2.3, NOx 0.15)
EU4 European exhaust-gas standard, valid from 2005 (levels: HC 0.1, CO 1.0, NOx 0.08)
EUI Electronic unit injector, injection nozzle of pump-nozzle system (diesel injection)
EUP Electronic unit pump, diesel pump of pump line nozzle system (diesel injection)
EURO3 European exhaust-gas standard, valid from 2000 (levels: HC 0.2, CO 2.3, NOx 0.15)
EURO4 European exhaust-gas standard, valid from 2005 (levels: HC 0.1, CO 1.0, NOx 0.08)
EUV Electro-reversing valve
EV Injection valve or Inlet valve of pressure control valve or Inlet valve of ABS system
EV1 Injection valve for high pressure
EV2 Injection valve for low pressure
EVA Electrical full-load stop or Emergency valve assistance, safety valve
EVAP Fuel vapor emission control
EVE Electronic distributor injection system (special engine control)
EVR Electronic vacuum regulator
EWD Single-coil actuator, servomotor with one winding
EWL External warning lamp
EWM Electronic selector-lever module. Control unit in Mercedes, usually proper name
EWMA Exponential weighted moving average, misfire detection during last 10 driving cycles
EWS Electronic immobilizer
EX Exhaust (or outlet, exhaust-gas recirc. valve, exhaust manifold)
EZ Electronic ignition, usually proper name
EZE Electronic central control unit, usually proper name
EZF Electronic ignition system, map-controlled
EZF-H Electronic ignition system with map, trigger by Hall sensor
EZF-I Electronic ignition system with map, trigger by inductive sensor
EZK Electronic ignition with knock control
EZ-K Electronic ignition timing with knock controls, proper name
EZL Electronic ignition system with characteristic curves
EZL-H Electronic ignition with characteristic curves, trigger by Hall sensor
EZS Electronic ignition switch
EZV Electronic ignition timing
F France
F/P Fuel pump
FA Front axle
FAB Failcode Airbag. Output line for error codes for airbag system (Mazda)
FAC Failcode Air Conditioning. Output line for error codes for air conditioner (Mazda)
FAP Accelerator pedal or Vehicle analysis protocol. Log maintained by tester during diagnosis. Can be printed and given to vehicle owner as evidence of repairs performed..
FAS Driver-assistance system
FAT Failcode Automatic Transmission. Output line for error codes for transmission control (Mazda)
FB Fast burn, rapid spread of flame front or Start-of-delivery, key parameter in diesel injection systems or Remote control
FBA Parking-brake system (usually hand brake)
FBB Start-of-delivery blocking
FBG Start-of-delivery sensor
FBKW Crankshaft angle at start-of-delivery
FBN Start of delivery, normal
FBR Start-of-delivery control
FBS Driving enabling system (Mercedes), or Failcode Brake System. Output line for error codes for ABS system (Mazda)
FBV Parking brake valve
FC Fault (error) code
FCKW Chlorofluorocarbon (CFC). Gaseous chemical compound that destroys the ozone layer. Contained in old refrigerants (R12) for air conditioners.
FCV Fuel cell vehicle. Vehicle with fuel-cell drive, up to now only a Ford prototype.
FD Date of manufacture
FDI Fuel direct injection, gasoline direct injection, refer also to GDI
FDR Trip computer or Vehicle dynamics control
FDS Ford diagnostic system
Delivery units, parameter for determining delivered fuel amount
Front Electrical Centre
FEN Failcode Engine. Output line for error codes for engine control unit (Mazda)
FES Spark energy control
FFG Accelerator pedal
FFR Vehicle master computer. Diagnostic gateway in vehicle, installed in combined instruments or central electrical system. Also contains the immobilizer.
FGB/AGB Speed limiter / automatic speed limiter, usually proper name
FGB/GBA Speed limiter / speed limiting system, usually proper name
FGG Speed sensor
FGR Speed control, usually proper name
FH Power window
FHE Road and obstacle detection
FHM Power window motor
FI Filter
FICD Fast-idle control device
FIN Finland
FIS Vehicle information system. Product designation (such as FIS 215)
FJI Fiji Islands
FKT Function
FKTSCH Function switch
FLA Vehicle performance analysis, product name for performance test stand (Bosch), or Spring-loaded idle stop
FM Vehicle management
FMN Delivery volume normal
FMVSS Federal motor vehicle safety standard
FN Vehicle level
FP Accelerator pedal or Delivery pump
FPK Freely programmable combined instruments
FPM Accelerator pedal module
FPR Fuel pump relay
FR FR signal: provides engine or engine/transmission control unit with information about generator load.
FRS Freewheel pulley
FS Driving-mode switch or Driver side
FSA Vehicle system analysis, product name for engine tester (Bosch)
FSD Folding sunroof
FSG Chassis control unit or Fill-level sensor
FSK Frequency shift keying
FSR Driving stability control
FSS Delivery signal sensor, or Flexible service system
FTCO Flat tachograph (new, flat design), Mercedes
FV Filling valve
FWA Chassis analysis. Sometimes also used as product designation (such as FWA 400)
FWI Vehicle-travel pulse number
FZ Vehicle
FZG Vehicle
FZK Vane compressor
FZR Vehicle controller, ESP system component
G g: Acceleration of gravity, or gram, physical unit G: G-signal : crankshaft signal for TDC, 4 signals for the control unit per distributor rotation
G/SEC g/sec: grams per second, unit
G/ZYL g/Zyl: grams per cylinder, unit for mass per cylinder
GA Basic adaptation or Guarantee
GATES Global automotive telematic standard
GB Yawing moment restriction or Great Britain
GBA Seat belt positioner drive
GBR Seat belt positioner
GDB Regulated differential brake
GDI Gasoline direct injection, designation for petrol direct injection systems or vehicle models with this system. Usually proper name.
GDL Gas pressure lamp (Audi)
GDV Constant pressure valve
GEN Generator
GER Germany
GGF ggf.: possibly, if necessary
GGS Transmission group switch
GHD Housing cover
GID Graphic information display (Opel)
GK Glow plug
GM Basic module, or Gear motor, or General Motors, proper name (name of vehicle manufacturer)
GMA Yawing moment buildup delay
GMR Mixture regulator
GND Ground
GOL Persian Gulf states
GPS Global Positioning System, satellite system for locating a vehicle
GR gr: large Gr: Group GR: Gas retention, or Greece
GRA Speed control system. Alternative term for cruise control.
GRV Constant-volume valve
GS Independent electronic transmission control, usually proper name, or Belt tensioner
GS 1.2 Electronic transmission control, Version 1.2, system name, proper name
GSG Speed sensor
GSH Gas sensor hydrocarbon, hydrocarbon sensor
GSK Sheathed element glow plug
GSM Global system for mobile communication
GSR Belt tensioner, usually proper name
GSS Transmission shift lock or Seatbelt buckle switch
GST Stepped start volume
GSY Speed symbol. Specification on tyres for allowable speed, alphabetic. See also Speed Index
GUS Belt tensioner or Commonwealth of Independent States (CIS)
GW Gateway. PC or computer that connects and controls data exchange between two networks.
GWK Transmission converter clutch
GZS Glow duration control unit
H h: hours H: hexadecimal number, or stroke, or Hungary
HA Hydraulic stop or Rear axle or Hydraulic modulator for ABS
HAC Height compensation
HAI Hot-air inlet
HAS Hand brake switch
HAU Automatic heating
HBA Hydraulic brake assistant or Hydraulically operated equalisation or Auxiliary brake system
HBZ Master brake cylinder
HC High compression or Version with high compression ratio or Hydrocarbon
HD Heating wire or Lifting roof
HDC Hill descent control. Special system that maintains speed downhill. Works using brake intervention at about 5 mph (8 km/h) (BMW and Rover offroad vehicles)
HDEV High-pressure injection valve
HDF Remote boot-lid release
HDI High-pressure direct injection
HDK Half-differential short-circuit ring travel sensor
HDP High-pressure pump
HDS Urea metering system, used with diesel vehicles to prevent or reduce soot emissions
HE Main injection
HEGO Heated exhaust-gas oxygen sensor
HEI High performance ignition system, transistorized ignition, contactless ignition
HEV High-pressure injection valve
HF High frequency
HFG Hand-operated gas delivery, for example in special vehicles for handicapped drivers
HFM Hot-film air-mass sensor or Special engine control in which load detection takes place via a hot-film air-mass sensor
HH HH division, 4/4 division of brake circuit: circuits 1 and 2 brake all wheels.
HHC Hill Holder Control, ESP system component
HHT Hand-held tester (such as KTS500 or PMS100)
HIC Hot idle compensation
HID Hill descent (sensor). Sensor that registers downgrades or vehicle rolling. See HDC.
HK Height correction or Hong Kong
HKD High-voltage trigger diode, special diode installed in ignition coils
HKZ High-voltage capacitor ignition
HL Left rear
HLM Hot-wire air-mass sensor
HO2S Heated oxygen (O2) sensor
HP Hydraulic pump
HPA hPa: hectopascal, physical unit
HPDI High pressure direct injection
HPI High-pressure injection. Direct-injection petrol engine used in Citroen and Peugeot. Comparable with GDI.
HR Hybrid control, or Right rear, or Croatia
HRA Rear window washing system
HSCAN High-speed controller area network. CAN bus with high transmission rate (Opel). See also CAN, LSCAN, and MSCAN.
HSPV Hydraulic injection timing device
HSV High-voltage distribution or Hydraulic start lock
HT HT division. 4/2 division of brake circuits: circuit 1 brakes all wheels, circuit 2 the front wheels
HU Major inspection
HW Hardware
HYAB Hydraulic shutoff device
HZ HZ: Master brake cylinder Hz: hertz, physical unit
HZR Heating control. Simple type of air conditioner.
I Italy
I1 Incremental system with one sensor
I2 Incremental system with two sensors
IAC Idle air control, i.e. idle speed control, for injection engines
IAM Independent after-market. Service or spare-parts dealers independent of vehicle manufacturer.
IC Integrated circuit
ICC Intelligent cruise control, Nissan distance control system; see also ACC.
ICE Ignition control electronics, electronic ignition system
Ignition control module, or Integrated chassis management, BMW vehicle-dynamics control with trend-setting technology
Infotainment Module
ID Identifier, bei CAN-Bus-Systemen eine Art Address-Byte, das angibt, für wen ein Datenblock bestimmt ist oder Identifikation
IDI Indirect (diesel) injection
IDIS Integrated driver information system, similar to navigation system
IDS Interactive dynamic driving system
IFS Inertia fuel shutoff. Safety fuel shutoff, or Independent front-wheel suspension
IFZ Infrared central locking
IG Pulse or increment transmitter, or Ignition
IHE Integrated hydroelectronics unit. Control electronics, hydraulic generator, and electric motor in Citroen Hydraktiv chassis.
IHKA Integrated heating and air conditioning system (BMW)
IHR Heating control, usually proper name
IIA Integrated ignition system
IL Israel
ILV Integrated quiet-running system
IMA Integrated engine assistant (special Honda engine control), or Injector quantity analysis
IMM Immobilizer
IMMO Immobilizer
IMP Pulse(s)
IN Inlet (intake) manifold or valve
INA Information display for ASR systems
IND India
INFOANZ Information display for ASR systems
INJ Injector. Injection jet or valve in Common Rail diesel system
INT Integrator

Central injection

Instrument Panel Body Electrical Centre
IPS Intelligent Protection System, integrated two-stage airbag system with retractable pedals, head/shoulder airbags, and active headrests. Used in Ford Mondeo.
IR Individual control with commercial-vehicle ABS systems, or Infrared, or Iran
IRF Interior filter
IRM Individual control, modified, with commercial-vehicle ABS systems
IRQ Iraq
IRS Interior protection
IS Iceland
ISA Idle speed correction or Intelligent speed adaptation: Use of a GPS system and traffic-sign database to automatically regulate speed (system still in test phase)
ISC Idle speed control or Idle compensation
ISDN Integrated Services Digital Network: digital telephone and data network with integrated services
ISF Vehicle information system
ISIS Intelligent safety system. System with multiple airbags, pyrotechnically triggered headrests, seat-belt tensioners and intelligent electronics (BMW)
ISO International Organisation for Standardisation
ISO-EGO Isolated Exhaust Gas Oxygen Sensor, isolierte unbeheizte Lambdasonde (mit Massekabel)
ISO-HEGO Isolated Heated Exhaust Gas Oxygen Sensor, isolierte beheizte Lambdasonde (mit Massekabel)
ISS Joint venture (Bosch, Michelin) for developing integrated vehicle dynamics systems
ISU Intelligent switching unit (Siemens)

Intelligent traffic guidance system (Mercedes)

In Vehicle Local Area Network
IWG Inductive travel sensor
IWZ Incremental angle/time sensor, rotation-angle sensor
IZA Integrated ignition system
IZV Infrared central locking
J Japan
JA Jamaica
JET Jet, Jetronic: injection system, usually proper name
JOBD Japanese OBD, OBD standard for Japan
JTS Jet thrust stoichiometric. Direct-injection petrol engine (Alfa)
JW Company car(s)
K k: small K: channel K-line: bidirectional line between control unit and tester
KA Knee airbag
KAM Keep-alive memory
KAT Catalytic converter
KB Wire harness
KBA Federal Motor Vehicle Office (Germany)
KBZ Combination brake cylinder
K-CAN Body CAN bus. Low-speed CAN bus for comfort-system and body electronics. See also PT-CAN and SI-BUS.
KD Kickdown or Customer service
KDS Kickdown switch
KE Continuous injection, usually proper name
KE-MOTRONIC Continuous electronic injection system, usually proper name
KEN KEn: Jetronic, continuous, with electronic extended-function unit, n=version, usually proper name
KF Fuel filter
KFB Fuel filter, petrol or Comfort zone
KFMG Continuous delivery-volume meter
KFZ Motor vehicle
KG kg: kilogram, physical unit, or Keyless Go (access to vehicle and engine start without key)
KG/H kg/h: kilograms per hour, unit
KGE Crankcase ventilation
KIW Combined instruments with service-interval indicator. See also SIA.
K-JETRONIC Continuous injection system, usually proper name
KL KL or Kl: Terminal
KLA Automatic climate control
KM km: kilometer, physical unit KM: small engine
KMA Continuous volume analysis, product name (Bosch)
KMM Continuous volume meter, checks fuel delivery
KMMG Continuous volume meter, closed
KMV Refrigerant compressor
KOM Commercial bus and rental vehicles
KOMP Component
KPA kPa: kilopascal, physical unit
KPN Kpn: Motronic (load detection occurs via intake manifold pressure, n=Motronic version, usually proper name)
KR Anti-knock control
KRF Kraftstoffrückführventil (Diesel)
KRS Anti-knock control interface or Fuel return valve
K-RWG Short-circuit ring sensor
KS Fuel reservoir, or Knock sensor
KSA Kingdom of Saudi Arabia
KSB Cold-start accelerator, with distributor injection pumps
KSE Child-seat detector
KSH Cold-start aid
KSP Fuel reservoir
KSS Cold-start control
KSV Cold-start valve
KSZ Fuel distributor or distribution
KTF Fuel temperature sensor, or Coolant temperature sensor
KU Clutch
KU/GN Clutch/transmission neutral position
KUKO Coupling head
KVA Fuel consumption gauge
KVD Fuel evaporation
KVR Fuel distributor tube
KVRS Evaporative emission-control regeneration system, also referred to as tank ventilation system
KVRV Fuel evaporation regeneration valve, tank ventilation valve
KVS Fuel distributor piece
KW kW: kilowatt, physical unit KW: crankshaft or crankshaft angle or shortwave (radio)
KWH kWh: kilowatt-hours, physical unit
KWP 2000 Keyword Protocol 2000, log for transmitting diagnostic data
KWS Comfort immobilizer
KWT Kuwait
KX Kx: Jetronic, continuous, with oxygen sensor control, usually proper name
KZS Capacitor intermediate storage
L l: liter, physical unit, or left L: left L-line: unidirectional line between control unit and tester
L/H l/h: Liters per hour, unit
L/KM l/km: liters per kilometer, unit
LAM Idle emissions measurement
LAV Luxury activity vehicles (vehicle classification, such as Lexus RX 300)
LC Low compression, or Version with low compression ratio
LCD Liquid crystal display, usually proper name
LDA Boost-pressure-dependent full-load stop, with distributor injection pumps
LDF Boost-pressure sensor
LDR Boost-pressure control, or Idle speed control
LE2-JET Petrol injection, LE-Jetronic, 2nd generation, usually proper name
LED Light-emitting diode, usually proper name
LEN LEn: Jetronic, intermittent, covers European functionality, n=version, usually proper name
LER Idle limit-speed control
LEV Low-emissions vehicle. Designation for vehicles with low emissions level. See also NLEV, SULEV, TLEV, ULEV, and ZEV.
LFB Load-dependent start-of-delivery, with distributor injection pumps
LFR Idle compensation
LFT Air temperature sensor, or Long (term) fuel trim (to counteract aging symptoms). See also LTFT.
LHA Air-side automatic heater
LHD Left-hand drive
LH-JETRONIC Same as L-Jetronic with hot-wire air-mass sensor, usually proper name
LHN LHn: Jetronic with hot-wire air-mass sensor, intermittent, n=version, usually proper name
LI (also li:) Left, or Load index, number indicating tyre load capacity
LIA Lift axle
LIM Sedan
L-JETRONIC Electronically controlled injection system (with direct air-mass measurement), usually proper name
LKE Load piston unit
LL Idle, engine operating state or Left-hand drive or LL division, triangular division of brake circuits: 2 circuits in front, one in rear
LLDRAN Idle speed increase
LLK Charge-air cooling
LLR Idle control (diesel systems)
LLRA LLRa: Idle control with adaptive pilot control
LLS Idle actuator, or Idle switch
LL-STAB Idle stabilization
LM Air-flow sensor (also LMM)
LMF Light-alloy rims
LMM Air-mass sensor, or Air-flow sensor
LMS Air-mass sensor
LN Ln: Jetronic with air-flow sensor, intermittent, n=version, usually proper name
LOS Emergency program (EEC IV)
LP Perforated plate
LPG Liquefied petroleum gas, fuel for vehicles with gas-powered engines
LPS Circuit board circuit
LPT Printer port or interface on PC
LR Oxygen sensor control
LRA LRa: oxygen sensor control with adaptive pilot control
LRD Load response drive, alternative multifunction control
LRR Smooth-running control, or Long-range radar (component of ACC system with detection range up to 120 m)
LRS Load response start, alternative multifunction control
LS Release switch or Oxygen sensor
LSCAN Low-speed controller area network. CAN bus with low transmission rate (Opel). See also CAN, MSCAN, and HSCAN.
LSD Limited-slip differential
LSF Oxygen sensor, planar (flat sensor)
LSH Oxygen sensor, heated
LSM Oxygen sensor for lean operation
LSP Longitudinal lock shutoff
LSU Wideband oxygen sensor, planar type
LSZ Light-switching centre
LT Model designation for VW Transporter, proper name
LTCC Low temperature cofired ceramic, multilayer ceramic technology
LTF Air-temperature sensor
LTFT Long-term fuel trim (to counteract aging symptoms). See also LFT.
LTG Line
LTR Liter, physical unit, often also ltr, L
LUN LUn: Jetronic, intermittent, with USA functionality, n=version, usually proper name
LWL Optical fiber
LWR Headlight vertical aim control
LWS Steering wheel angle sensor. Component of ESP system, determines steering-wheel rotation
M M: Motronic, usually proper name, or Mechanical or Mechanical fan or Centre m: Centre or Manual
M/S2 m/s²: meters per second per second, physical unit for acceleration
M3/H m³/h: cubic meters per hour, unit
MA mA: milliampere, physical unit MA: Mono-Motronic, petrol injection system, usually proper name
MAEL MaEl: earth (ground) electrode (spark plug)
MAF Mass airflow sensor
MAL Malaysia
MAP Manifold absolute pressure or Intake manifold pressure sensor
MAR Quantity compensation control
MAS Control unit for engine assembly
MAT Manifold absolute temperature
MAX Maximum
MBAR mbar: millibar, physical unit
MBS Engine-brake switch
MBZ Diaphragm brake cylinder
MC Microcomputer or Medium compression
MCC Micro Compact Car. DaimlerChrysler subsidiary that manufactures the Smart vehicle.
MDA Engine speed increase
MDF Mass of wheel-speed sensor, usually with an indication of the particular sensor (left front, right front, etc.)
MDR Membrane pressure control
ME Motronic with electronic gas pedal, usually proper name, or Control unit for volume regulation in diesel systems, usually proper name
MEA Middle East
MEAB Mechanical shutoff device (diesel EDC). In newer systems, the shutoff is electrical (see ELAB).
MECH. Mechanical
MED Motronic with ETC and petrol direct injection
MEG Motronic with ETC and transmission control
MEINS Meins: Injection volume (in mg/stroke or mg/s)
MEN Monitor engine (output line for engine diagnostic data)
MEP Mean effective pressure
MES Mechanically enabled start volume
MEX Mexico
MF Measurement window
MFA Measurement window, start or Multifunction display
MFD Multifunction display
MFE Measurement window, end
MFI Multipoint fuel injection (electronic)
MFI-C Continuous multipoint fuel injection (electronic)
MFI-I Intermittent multipoint fuel injection (electronic)
MFI-S Sequential multipoint fuel injection (electronic)
MFL Multifunction steering wheel
MFR Multifunction control
MFS Multifunction sensor
MFU Multifunction clock
MG Manual transmission
MG/H mg/H: milligrams per stroke, unit
MG/ZYK mg/Zykl: milligrams per cycle, unit
MGND Engine ground (earth)
MHDI Mechanical high-voltage distribution ignition
M-HEAT Mirror Heating, Spiegelheizung (Opel)
MI mi: Miles, physical unit MI: Malfunction indicator or Main injection (see also HE)
MIC Microplex (Marelli)
MICROPLEX Fully electronic ignition system with knock control
MID Multifunction information display
MIEL MiEI: Middle electrode (spark plug)
MIL Malfunction indicator lamp
Main Instrument Unit
MJ Mono-Jetronic, usually proper name or Model year
M-JET Mono-Jetronic, usually proper name
MK Motronic with continuous fuel metering, usually proper name
MKV Multiplicative map adjustment, or Fuel ratio mixture
ML Motronic with flap air-volume sensor, usually proper name
MLA Multiple link antitheft system (system-wide theft protection)
MLD Mechanical load-peak damping
MLN MLn: Motronic based on air-flow sensor, n=version, usually proper name. See also LM.
MM mm: millimeter, physical unit
MM3/H mm³/H: cubic millimeters per stroke, unit
MMI Engine torque, actual value or Man-machine interface (Porsche designation)
MMM Multipath map matching (navigation system)
MMS Engine torque, nominal value
MMV Quantity solenoid valve
MN Mn: Motronic, universal load detection (HLM, LM), n=version, usually proper name
MNEFZ Modified new European driving cycle (exhaust-gas test cycle). See also NEFZ.
MODIC Mobile diagnosis computer (BMW diagnostic tester)
MOLIS Modular lights system. LEDs in modular system for rear lights, for example (BMW)
MOST Media oriented system transport. Usually in conjunction with a bus system (MOST bus), via which various control units in the vehicle communicate with each other.
MOT Engine tester, product name (Bosch) or Engine test
MOT/DME Digital Motor Electronics (Motronic)
MOZ Engine octane number. Expresses the knock resistance of petrol fuel (US variant of ROZ).
MP Motronic with intake manifold sensor, usually proper name
MPA MPa: megapascal, physical unit
MPFI Multi-point fuel injection, electronic, usually proper name
MPH mph: Miles per hour, physical unit
MPI Multi-point injection, fully electronic engine control, usually proper name
MPN MPn: Motronic in which load detection is via intake manifold pressure, n=version, usually proper name
MPV Multi-purpose vehicles (Mazda). Comprises the group of vans and small panel trucks.
MR Engine relay or Engine control for ASR
MR-DF Speed sensor with magnetoresistive measurement
MRS Multi-restraint system. Temic or BMW system consisting of belt tensioner, belt force limiting, airbags, and safety battery terminal (see SBK).
MS ms: millisecond, physical unit MS: Engine control or Diesel systems with electronic volume- and start-of-injection control
MSA Designation for diesel injection systems having an electronic volume control, start-of-injection control, and exhaust-gas recirculation. Systems without exhaust-gas recirculation are designated simply as MS.
MSCAN Medium-speed controller area network. CAN bus with medium transmission rate (Opel). See also CAN, LSCAN, and HSCAN.
MSG Engine control unit
MSR Engine drag torque control, usually proper name
MST Measurement and control unit
MSTS Microprocessor spark timing system, electronic ignition with map control (ELZ), or Multi spark timing system, function as for EST. MSTS, however, is not an integrated part but rather a separate ignition control unit
MT Manual transmission or Mechanical transmission or Volume divider
MTCO Tachograph
MTM Engine measurement technology module
MUD mUD: With vacuum
MUX Multiplexer or multiplex signal
MUXPORT Multiplexer-Port, Schnittstelle am PC, an die der Multiplexer angeschlossen ist oder angeschlossen werden kann
MV mV: millivolt, physical unit MV: Solenoid valve
MVEG Motor vehicle emission group, exhaust-gas classification for passenger cars
MVL Lift axle valve with electronic air-cushioning system
MVLDR Solenoid valve for boost pressure control
MVN Level valve with electronic air-cushioning system
MVS Solenoid valve control unit
MW AM (radio), or Measurement
MY Model year
MZ Magneto ignition
MZV Microprocessor-controlled ignition adjustment
N n: RPM, or normal N: Selector-lever position (Neutral) for automatic transmissions, or Norway
NA Auxiliary drive or Netherlands Antilles
NAS Auxiliary drive switch
NAV Navigation or Navigation system
NB Commercial-vehicle brake
NBE Proximity detector
NBF Needle lift sensor (diesel)
NBS Needle lift sensor (diesel)
NCAP New Car Assessment Program, better known as EURO-NCAP, association for conducting more demanding crash tests (with participation of vehicle manufacturers)
NDS Neutral drive switch, activated when automatic transmission selector lever is in neutral position
NE NE: After-injection Ne-Signal: Engine RPM signal, 24 AC signals sent to control unit per distributor rotation
NEDC New European driving cycle (procedure for fuel consumption measurement). See also NEFZ
NEFZ New European driving cycle (procedure for fuel consumption measurement). See also NEDC
NF Low frequency, or audio frequency
NFZ Commercial vehicle (lorry, truck)
NHG Needle-displacement sensor (diesel systems)
NHU Navigation head unit. Opel navigation control unit.
NIC Nicaragua
NKW Lorry (truck)
NKW-ABS Anti-blocking system for lorries (trucks) with air brakes
NL Netherlands
NLEV National low-emission vehicles. US approval level for vehicles that must fulfil the current requirements. See also LEV, SULEV, TLEV, ULEV, and ZEV.
NLK Follow-on piston
NLS Needle lift sensor (diesel)
NM Nm: Newton-meter, physical unit
NM/S Nm/s: newton-meters per second, unit
NMOT Nmot: Engine RPM
NOE Nitrogen oxide emission
NOX NOx: Nitrogen oxides
NPB Delivery volume normal test stand (special tester for injection pumps)
NR Number, or Level control, or Natural rubber (often processed for use in truck tyres).
NRZ NRZ format: Non-return-to-zero, transmission or pulse form for square-wave pulses and signals
NS Fog light(s)
NSW Fog lights
NTC Negative temperature coefficient, thermal resistor with negative temperature coefficient, so-called hot conductor
NTC II Idle speed increase
NTC1 Intake air temperature (in °C)
NTC2 Engine water temperature (in °C)
NVF Navigation and traffic control
NW Camshaft
NWS Camshaft timing
NZ New Zealand
O2 Oxygen
OAI Octane adjust input
OBD On-board diagnostics or off-board diagnostics, vehicle-internal diagnosis with internal or external test unit, usually proper name
OBF Upper control panel. Above or on the dashboard, some vehicles have switches or buttons, such as for the rear-window defogger. These elements together comprise a control panel, which is referred to as the upper control panel to distinguish it from another control panel near the gearshift lever or below the radio.
OBM On-board measurement
OC Oxidation catalytic converter
ODFT Sensor for oil pressure and temperature
ODS Automatic overdrive control
OEDS Oil pressure switch
OEF Location of missing vehicles (via GPS)
OEM Original equipment manufacturer
OES Original equipment service. Service or spare parts via the vehicle manufacturer.
OFFSET-V Voltage offset
OG Upper limit or Upper tolerance limit
OHC Overhead camshaft. Camshaft situated above the cylinder head. Often used in engine designations.
OHV Overhead valves (the camshaft is therefore underneath)
OMM Surface micromechanics
OOP Out-of-position detection
OP Oil pump
OPC Opel Performance Centre. Centre for automotive sports (Opel).
OR Logical OR operation
OSRVM Outside rear-view mirror (Opel)
OT Top dead centre
OTA Oxygen/titanium emissions sensor. Titanium oxide sensor. See also OZA.
OTF Oil temperature sensor
OUD OUD: Without vacuum
OUT Designation on diesel pump for excess-flow restriction screw
OZ Octane rating. See also ROZ.
OZA Oxygen/zirconium emissions sensor. Zirconium oxide sensor. See also OTA.
P Pressure, or Power train (used with OBD error codes, for example), or Portugal
PA Pa: pascal, physical unit of pressure. See also HPA, KPA, and MPA. PA: Parking assistant
PAG Polyethylene glycol oil, low-temperature oil
PAM Parking assistant module (Opel)
PANS Pans: Intake air pressure (in hPa)
PAS Peripheral airbag sensor (side airbag)
PASE Passive start and entry. Keyless access to car and engine start (Siemens system). Also called Keyless Go (Mercedes, for example)
PATA Passive button. Button in vehicle with which a function can be set to the passive (off) state
PATS Passive antitheft system
PB Pb: chemical symbol for lead (Latin: plumbum)
PBM Pulse width modulated, signal processing method (prior to sending), usually proper name
PBSL Park brake shift lock. Selector lever lock for automatic transmission (Opel)
PC Power control or Personal computer
PCM Power train control module or Porsche Communication Management, central multimedia control unit for various functions
PCU Pump control unit (diesel systems), or Power control unit, hybrid-drive control (Honda)
PCV Positive crankcase ventilation, closed crankshaft ventilation
PD Pump-nozzle
PDAS Dynamic 4-wheel control, usually proper name
PDC Park distance control. Parking aid, often proper name, or Pre-drive check (testing of EHB systems)
PDE Pump-nozzle unit (new designation is UIS)
PDM Passenger door module (Opel)
PDOE Nozzle opening pressure
PEHKS Pedestrian protection hood kinematics system. Ford mechanical system that raises the hood (bonnet) in the case of an impact (such as hitting a pedestrian). See also POBSY.
PES Polyellipsoid system (headlight technique)
PES-SW Polyellipsoid headlight(s)
PFA Particle filter system
PFI Port fuel injection, inlet-channel injection
P-FP p-FP: Delivery pump pressure.
PG Phase sensor
PH Pressure high, high pressure
PHI phi: Greek letter used to designate angles.
PHS Park heater system
PI Pilot injection. See also POI, MI, and HE.
PID Parameter identifier, part of CARB, code for current values or similar parameters, usually proper name
P-IN p-in: Delivery pressure
PIP Profile ignition pickup, ignition output circuit (Ford) or Signal of Hall sensor for crankshaft RPM and position
PJ Pilot-Jection
PKW Passenger car
PL Country code for Poland, or Pressure low, low pressure
PLA Pneumatic idle increase or Pneumatic idle stop
PLD Pump-line-nozzle, diesel injection technique (new designation is UPS)
PLR Pneumatic idle speed control
PLU Pierburg measurement cell, or Pierburg Aviation
PM Pump motor
PML Parametric steering, assisted vehicle steering. The related data (parameters) are stored in the control unit.
PMR Private mobile radio
PMS Engine control with load detection via intake-manifold pressure (Mercedes) or Inlet-channel injection
PNAB Pneumatic adjustment device
PNABU Pneumatic adjustment device, vacuum-operated (Bosch KH)
PNABUE Pneumatic adjustment device, pressure-operated (Bosch KH)
PNG Papua New Guinea
POBSY Pedestrian protection optimised bumper system. Ford bumper system made from energy-absorbing foam plastics to protect pedestrians.
POI Post-injection. See also PI, MI, and HE.
POTI Potentiometer, variable resistance
PPG PPG module: Periphery program module; module containing control unit diagnostic programs or other CompacSoft programs, proper name
PPM ppm: parts-per-million, unit
PPS Pedal position system, or Pedal position sensor
PRC People's Republic of China
PRG Program
PROG Programming input
PROM Programmable read-only memory, usually proper name
PRS Programmed restraint system. Reduces the seat-belt tension and thus upper-body injuries (Renault)
PS Test step or Pump control or Horsepower, unit of work performed by motor vehicles
PSD Pump control with diagnosis or Porsche limited-slip differential, usually proper name
PSE Pneumatic system electronics, electronically controlled pneumatic system
PSG Pump control unit
PSI psi: Pounds per square inch, physical unit
PSM Porsche Stability Module. Porsche-specific designation for ESP.
PSP Power steering pressure
PSPS Power steering pressure switch
PSV Partial intake-manifold pre-heating
PT Power train
PTC Positive temperature coefficient, thermal resistor with positive temperature coefficient, so-called cold conductor, or PTC heating element in intake manifold for delivering heat for evaporation
PT-CAN Power train CAN bus. High-speed CAN bus for drive-train electronics. See also K-CAN, SI-BUS.
PTS Park-Tronic System. Parking aid. See also PDC.
PV Testing instruction
PVS Vacuum switch
PWG Pedal position sensor, usually proper name
PWL Power window lifter
PWM Pulse-width modulation, special signalling form used to determine pulse-duty factors on components (for example, triggering of tank ventilation valve is usually based on such a factor)
PWR Pulse rectifier
PY Paraguay
Q Quantity, usually of fuel
Q1 Fuel quantity for cylinder 1. Similarly Q2, Q3, etc.
Q-AVG Quantity average. Mean of (fuel) quantity of all cylinders
QB Quality assessment
QGS Quick glow system. Rapid pre-heating system for diesel engines.
QHS Quick heat system. Rapid diesel pre-heating system.
QM Quality management
Q-OVER Q-over: Overflow quantity
QS Quality assurance
QSF Average function
QSL Quasi select low
QUADR Quadrifoglio, Alfa Romeo model designation
RA Rear axle, or Argentina
RAIL Common Rail, high-pressure distribution line with Common Rail diesel systems
RAM Random access memory, read/write memory of a processor
RAS Rear-axle steering. Actively steered rear axle used in buses, for example.
RB Robert Bosch
RC Remote control, or China (Taiwan)
RCA Republic of Central Africa
RCH Chile
RDK Tire pressure check system, usually proper name
RDS Rail pressure sensor or Radio data system
RDU Tyre pressure monitoring
RDV Reverse-flow throttle valve
RDW Rest of the world (group in exhaust-gas classification)
RE Right (often "re") or Inline injection pump
REA Resonance detection
REC Rear electrical centre (Opel)
REL Relay
RF Radio frequency, radio signal
RFP Return pump
RFS Backup light(s)
RFT Run-flat tyre. Special tyre that can also be used in an emergency.
RG Route guidance (Travel Pilot)
RGS Route guidance standalone (Travel Pilot as standalone system)
RHD Right-hand drive
RHO rho: Greek letter, represents density (kg/m³)
RHV Static high-voltage distribution
RI Indonesia
RIV Control pulse method (diesel)
RKS Tire check system
Right-hand drive
Rear Left Door Module
RLFS Fuel supply system without reverse flow
RLV Reverse-flow valve
RM Reference mark
RME Rapeseed methyl ester, alternative fuel
RO Romania
ROK Republic of Korea
ROM Read-only memory. Program memory of processor, or other memory, that can only be read.
RON Research octane number, see also ROZ
ROPS Rollover protection system. Automatically extendable rollbar (Volvo)
ROV Rotating high-voltage distribution
ROZ Research octane number
RP In-line pump, or Philippines
RPA Flat tyre indicator
Revolutions per minute
Rear Right Door Module
RS Restraint system or Rotational speed sensor
RSC Run-flat system component. Tyres with emergency-running properties. See also RFT.
RSD Backflow throttle
RSV Check valve, prevents undesired reverse-flow of liquids or gases
RTI Radio Traffic Information, Verkehrfunk
RTM Smoke opacity measurement module, product name for exhaust-gas tester (Bosch)
RTR Reverse-flow temperature control
RU Soot concentration in exhaust
RUE Soot emission
RUEF Retrofit vehicle
RUM Soot amount
RUV Static high-voltage distribution, usually proper name
RW Control travel
RWAWS Control-travel evaluation circuit
RWD Rear wheel drive
RWG Control-travel sensor
RX Receive line (contrast with TX line).
RZ Wheel brake cylinder
S S: Sensor, or super (premium) grade fuel, or sport program (automatic transmission), or Sweden s: seconds
SAC Self-adjusting clutch. Transmits only the current engine torque
SACV Secondary air control valve
SAE Society of Automotive Engineers, US organization that prescribes standards, recommendations, or guidelines for technically implementing legal requirements (such as for engine oil, error codes, data transmission, etc.)
SAM Safety (or signal detection) and triggering module. Designation for Mercedes control unit.
SAS Side-impact protection
SAT Siemens adaptive transmission control
SAV Overrun cutoff valve, or Sport activity vehicles (for example BMW X5)
SB Star-of-injection, indicates when fuel injection actually starts (the start-of-delivery on the other hand is the time at which the fuel pump begins to deliver), or Control unit for start-of-injection control (diesel)
SBB Disc-brake lining
SBC Sensotronic Brake Control, part of EHB (electrohydraulic brake) system
SBE Seat-occupied detection
SBK Safety battery terminal. Part of airbag system. In the case of an accident, the battery is rapidly disconnected from the starter cable in order to prevent short circuits and reduce the risk of fire.
SBR Start-of-injection control
SBS Speech-based operation system (Porsche designation)
SCAN TOOL Tester for reading OBD error codes and other OBD data
SCC Safety car concept. Volvo concept for vehicle in which many safety features have been integrated
SCHR Steps, such as with a stepping motor
Smart-charged injection. Petrol direct injection (Ford)
Steering Column Lock
SCP Serial communication protocol, proper name
SCS Stability control system. Simplified form of ESP (Mitsubishi). Prevents vehicle tilting or skidding.
SCU Sensor and control unit. Control unit with integrated radar sensor, main component of ACC system.
SD Intake manifold pressure, or Sunroof, or Injection duration, or Control unit diagnosis
SDI Intake diesel injection
SDL Service diagnosis line, product designation for test line (Bosch)
Sunroof motor or Control unit diagnosis module
Sensing and Diagnostic Module (airbag)
SDS Intake-manifold pressure sensor
SDW Signal from anti-theft warning system
SEC Seconds, physical unit
SEFI Sequential fuel injection, usually proper name
SELECT HIGH Select-high control for commercial-vehicle ABS systems. The pressure level is geared to the wheel running with the higher coefficient of friction.
SELECT LOW Select-low control with commercial-vehicle ABS systems. Pressure level depends on wheel running with the lower coefficient of friction
SET CONTROLLER Program command related to controller
SFI Sequential multipoint fuel injection
SFT Short (term) fuel trim (lambda-parameter correction). See also STFT.
SG Control unit
SGP Singapore
SHD Sliding or lifting sunroof
SHR Select-high control for commercial-vehicle ABS systems. The pressure level is geared to the wheel running with the higher coefficient of friction.
SHZ Heated seat
SI Speed index (code letter for speed), or Silicon
SIA Service interval indicator. Shows the driver that oil change or annual inspection is required, for example. See also WIV.
Safety and information bus system. See also K-CAN and PT-CAN.
System Information Display
Sid Controller
SIH Sitzheizung
SIL Seat electrical system, left
SILA Signal lamp
SIM Safety information module. Component of ISIS system (BMW)
SIPS Side-impact protection system (Volvo)
SIR Seat electrical system, right.
SIS Service Information System, proper name or Series repair
SKF Spike characteristic. Relates to Porsche transmission controls.
SKO Compressor signal
SKT Scale units
SL Select low
Safety lamp
Secondary-air injection
Shift lever Module
SLO Slovenia
SLP Secondary-air pump
SLR Select-low control for commercial-vehicle ABS systems. The pressure level is geared to the wheel running with the lower coefficient of friction.
SLS Secondary-air system
SM Seat memory, or Stepping motor
SME Stepping-motor electronics
SNA Automatic momentum utilisation
SNR Part number or Record number
SO Safety switch, normally closed (actuator)
SO2 Sulphur dioxide. Pungent gas causing respiratory diseases. It is thus an aim to reduce the sulphur content in exhaust gases.
SOHC Single overhead camshaft
SOP Start of production
SP Safety testing, usually in conjunction with testing of brake system
Mirror drive
Sonic Park Assist
SPI Single point injection, usually proper name
SPL Noise level, or Sound-pressure level
SPM Mirror memory, usually proper name
SPOR Sporadic
SPOUT Ignition signal (EEC IV)
SPS Solar position sensor
SPV Injection adjustment (see also SV)
SR Side-based control
SRA Headlight wiper system
SRC Source (of data or audio signals, for example)
SRE Intake-manifold injection
Headlight wiper motor
Sun Roof Module
SRS Safety restraint system (generally includes airbag and seatbelt tensioner, normally controlled by a common control unit)
SS Safety switch, normally open (sensor 9)
SSA Automatic start/stop
SSD Steel sliding sunroof
SSG Seat control unit (Mercedes)
SSHD Steel sliding/lifting sunroof
SSS Stop/start system
SST Special tool or self-supporting tyre, tyre which supports itself and features limp-home properties
SSU Triggering device for side airbag
ST System tester
STAE Start external, external start switch
STAT Static
STC Stability and traction control
STFT Short-term fuel trim (for lambda-parameter correction). See also SFT.
STH Stationary-vehicle heater
STI Self-test input signal
STM Servomotor
STO Self-test output signal
STOE Stop external, external stop switch
SU Soviet Union
SULEV Super ultra-low emissions vehicle (group in classifying exhaust-emissions levels). See also LEV, NLEV, ULEV, TLEV, and ZEV.
SUS Slip threshold switchover
SUV Sport utility vehicles. Vehicle group comprising off-road-capable, leisure-activity sport vehicles and commercial vehicles with all-wheel drive (fun vehicles). Better suited for on-road than off-road. Examples: Mazda Tribute, Mercedes ML 320.
SV Injection adjustment (see also SPV) or Servo valve or Start valve
SVC Saab variable compression. The cylinder head is tilted in order to modify the compression ratio, or Speed volume control. Speed-dependent volume control for car radios.
SVG Seat adjustment transmission
SVM Seat adjustment motor
SW Headlight(s) or Software
Headlight washer
Steering Wheel Control
SWD Vibration damper
SWT Side wall torsion sensor. Detects longitudinal and transverse forces directly at the wheel during acceleration, braking, and in curves. Currently employed for quick-reaction ABS and ESP systems, in the future possibly for counteracting wind gusts.
SZ Opacity number, or Coil ignition, possibly with interrupt contacts or Switching-time program (determines switching time)
T t: (such as t-adj., time of adjustment) T: temperature (such as T-comp, compression temperature)
T.C.S. Ignition timing control system
T.O.C.S. Throttle valve control system
TA Traffic announcement, or Thorax airbag (BMW)
TAB Test Airbag. Excitation lead for airbag system (Mazda)
T-ABGLEICH t-adjust: time of adjustment
TAC Test Air Conditioning. Excitation lead for air conditioner (Mazda)
TANS Tans: Intake air temperature (in °C)
TAS Temperature dependent control, with distributor injection pumps, or Temperature dependent start-volume, with distributor injection pumps
TAT Test Automatic Transmission. Excitation lead for transmission control (Mazda)
TAU Automatic temperature system
TBB Drum-brake shoes
TBI Throttle body injection, central injection
TBS Test Brake System. Excitation lead for ABS system (Mazda)
TC Traction control, auxiliary function with ABS
TCE Trailer central electronic, central electronics system for trailer
TCM Transmission control module (Opel automatic-transmission control unit)
TCO Tachograph (Mercedes)
T-COMP T-comp: Compression temperature
TCS Traffic centre service
TCSA Temperature controlled spark advance
TCU Transmission control unit
TD TD: Time division, engine load signal tD: Transistor speed signal, square-wave signal supplying RPM for other systems such as transmission control
TDC Top dead centre, see also OT
TDI Turbo diesel injection
TDS Tank pressure sensor
TEC Total electronic control
TEE Tank installation unit
T-EIN t-ein: Build-up time
TELE-AID Telematic alarm identification on demand, accident notification


TEMP. SCH. Temperature switch
TEMPF Temperature sensor
TEN Test Engine. Excitation lead for control unit (Mazda), usually proper name
TES Thermo-electric switch or tank ventilation system (also referred to as evaporative emission-control regeneration system)
TEV Tank ventilation valve or Thermostatic expansion valve (heating/air conditioning)
TF Temperature sensor
TFA Test of radiator fan
TFI Electronic ignition switch (EEC)
THA Thailand
THS Toyota hybrid system. Hybrid of combustion and electrical drive, with electronic control.
T-HYBRID Hybrid temperature
THZ Tandem master cylinder. Master brake cylinder for hydraulic brakes.
TI ti: Injection signal (t=time, i=ignition)
TID Test identification data or Triple Info Display, driver information system in which certain data and information is displayed
TIM Time impulse
T-IN T-in: Inflow temperature (actual) T-in (nom.): Nominal inflow temperature
TIPTRONIC Porsche or VW electronic transmission control. The control can be operated via a small device on the steering wheel.
TKRAFT Fuel temperature (in °C)
TKU Technical customer documentation
TL tl: Engine load signal recorded over time TL: Partial throttle, engine operating state
TLA Temperature dependent idle increase, with distributor injection pumps
T-LASTPUNKT Time of load point
TLEV Transient low-emissions vehicle (group in exhaust-emissions classification). Comprises vehicles with low emissions levels. See also LEV, NLEV, SULEV, ULEV, and ZEV.
TLK Temperature dependent idle correction
TMB Door module, passenger side
TMC Traffic message channel
T-MESS Time or duration of measurement
TMF Door module, driver side
TMOT Engine temperature (in °C), usually determined from coolant
TMS Telematic system
TN tn: Signal from ignition with inductive peaks suppressed. Used for RPM detection for control unit and speedometer
TNA Signal output for engine speed.
T-OFFSET Time offset
T-OVER T-over: Overflow temperature
TP Throttle valve potentiometer (actuator)
Tempomat (cruise control)
Tyre Pressure Monitoring
TPMS Tyre pressure monitoring system, with pressure and temperature sensors at wheel (Opel/Teves)
TPS Throttle position sensor
TQ Time quantity (usually TQ signal). Fuel consumption signal.
TR TR: RPM information, or contact roller, or Turkey tr: Calculated RPM signal
TRACS Traction control system (Volvo)
TRUST Trundle stability
TS Temperature switch or Twin spark, double-spark ignition (Alfa Romeo)
TSG Tank level sensor or Door control unit
TSH Door lock heater
TSP Trailer stability program, ESP type system for trailers, designed to prevent trailer skid (Opel)
TSS Thermal protection switch
TSU Speedometer signal transformer
TSZ Transistor coil ignition with discrete components
TSZ-H Transistor coil ignition with Hall sensor
TSZ-I Transistor coil ignition with inductive sensor
TSZ-IZA Transistor ignition with ignition coil in distributor
TT TT division. Black-and-white division of brake circuits: one circuit in front, one in rear.
T-TOTAL t-total: Total measurement time
TUEV German vehicle-inspection authority
TV TV: Timing valve tv: Offset time of oxygen sensor control
TVA Temperature dependent full-load stop
T-VIS Toyota variable intake system (cut-in at 4500 rpm in 16-valve engines)
TVS Temperature dependent vacuum switch or Thermal vacuum switch
TVSV Temperature dependent vacuum switching valve
TWA Twin-wheel axle. Axle with twin tires on each side.
T-WAIT t-wait: Wait time
T-WARTE Wait time
TWC Three-way catalytic converter
TX TX line: Transmission line, in contrast to RX line
TZ Transistor coil ignition with hybrid component
TZ-H Transistor ignition with Hall sensor
TZ-I Transistor ignition with inductive sensor
TZS Thermal time switch
U Below, underneath or Voltage
United Arab Emirates
Ultrasonic Alarm Module
UB Battery voltage, supply voltage at terminal 30
U-BATT Battery voltage
UBF Lower control panel. Near the gearshift lever or below the radio, some vehicles have switches or buttons, such as for the rear-window defogger. These elements together comprise a control panel, which is referred to as the lower control panel to distinguish it from another control panel on or above the dashboard.
UBL Brake-light voltage
UCL Understeering control logic. ESP system used in Renault Megane.
UDB Vacuum limiter
UD-F Vacuum adjustment EARLY
UD-MODUL Vacuum module. Valve for switching and measuring intake manifold pressure
UDS Accident data memory (VDO), similar to black box in aircraft
UD-S Vacuum adjustment LATE
UEC Underhood Electrical Center, Opel designation for engine-compartment electronics module
UEDS Excessive-speed switch
UEGO Universal exhaust gas oxygen sensor, non-heated Lambda sensor
UERB Rollbar
UEV Excessive-flow valve

Lower limit Lower tolerance limit

Unité Centrale d'Habitaclé (Cabin Central Processor)
UIS Unit injection system, new designation for PDE systems (diesel injection systems with pump-nozzle unit)
U-KAT Unregulated catalytic converter (without oxygen sensor control)
ULEV Ultra-low emissions vehicle (group in exhaust-gas classification). See also LEV, NLEV, SULEV, TLEV, and ZEV.
ULW Ultra lightweight
UM Reversing valve (for ASR operation)
UMTS Universal Mobile Telecommunications System. Standard for the 3rd generation of mobile radio communications. Is to replace the analogue radio system over the long term.
UNI1 UNI2,Additional lines on universal adapter cable, used to read out flash codes or for special purposes
UP Unsaturated polyester. Thermosetting plastic used in body construction or to manufacture pressure-resistant containers.
UPA Ultrasonic parking assistant
UPS Unit Pump System, new designation for PLD systems
URS Rollover sensor, usually proper name
US Designation denoting basis on U.S. emission standards
USA United States of America
USB Universal serial bus. The USB interface permits simple connection of various peripherals to a PC.
USG Non-interrupting manual transmission. Two clutches (drive-off and load-shift) enable electronically controlled driving without shifting interruptions.
USV Change-over valve
UT Bottom dead centre
UUV Urban Utility Vehicle, Nutzfahrzeug für den Einsatz in der Stadt
UV Ultraviolet. Used mostly in conjunction with light or radiation.
UVR Voltage at valve relay
UVS Rollbar and variable sunroof control (Mercedes)
UW Voltage converter
UZ Voltage after ignition, terminal 15
V V: Volt, physical unit, or carburetor engine, or valve, or viscose, or fan, or front v: Front, or velocity
V/MS V/ms: volts per millisecond, unit for voltage per time.
VA Vorderachse
VAC Variant coding
VAF Air-flow sensor
VAG Volkswagen AG, vehicle maker, proper name
VAKU-SCH. Vacuum switch
VAN Vehicle Area Network. The VAN bus is a bus system that interconnects various components in the vehicle. This can be a CAN bus, but it can also be another type of bus.
VANOS Variable camshaft timing
VARILIS Variable lighting system (Hella)
VAT Intake-air temperature sensor
VC Variant coding
VCV Vacuum control valve
VD Choke valve
VDC Vehicle distance control or Vehicle dynamics control
VDV Vacuum delay valve
VE Distributor injection pump (series designation). See also VP
VERD. Verdeck (Cabrio)
VES Fully electronic radio ignition key
VEZ Fully electronic ignition system
VFD Vacuum fluorescence display
VFR Variable focus reflector (headlight)
VGWX Preset value if sensor fails
VIM Vehicle immobilizer
VIN Vehicle identification number, code stored in control unit
VIS Variable Intake System (Rover)
VK Valve body
VKP Programmable variant coding
VKS Variant coding with plug
VL Left front, or Full load, engine operating state
VLP Preliminary charge pump
VM Adjustment motor or Combustion engine
VOCS Voice control system
VP Distributor pump (usually factory-internal designation). See also VE
VPC Volvo Personal Communicator. SCC element with fingerprint sensor that detects the identity of the driver and makes driver-specific adjustments.
VR Right front or Distributor pump with radial piston
VRD Vario nozzle, nozzle with variable radius
VRM Valve feedback
VRS Relay supply voltage
VSA Vehicle stability assist. System similar to ESP.
VSC Voltage supply control. Battery management system (Mercedes)
VSG Composite safety glass
VSO Vehicle speed out
VSS Volts peak-to-peak, unit for special voltage values, measures difference between maximum and minimum voltage levels or Vehicle speed sensor, or Vehicle security systems
VSV Vacuum switching valve
VT Vacuum transducer
VTG Variable turbine geometry. The turbine has movable guide blades, which can be varied depending on the operating state of the vehicle. A turbocharger with variable turbine geometry offers the advantage that it is more responsive than a conventional turbocharger with fixed turbine geometry.
VTV Vacuum transmitting valve
VVA Variable valve actuation. Variable valve control between cams and valves. Operates electrohydraulically. Duration and width of opening can be varied (Fiat, Lancia)
VVC Variable valve control
VVL Variable valve lift
VVW Variable valve displacement
VW Compensating resistor or Volkswagen, vehicle maker, proper name
VZ Electronic ignition timing with static distribution
VZ-K Electronic ignition timing with static distribution and knock control
W/M2 W/m². Watts per square meter. Physical unit for solar radiation intensity
WAA Wiper blade
WALA Safety lamp
WAN Nigeria
WDS World diagnostic system (Ford tester)
WE Water injection
WEBER Weber petrol injection
WEO Western Europe except Germany
WFS Immobilizer
WHA Water-side automatic heater
WIG Wiper pulse transmitter
WIV Service interval extension. Under certain conditions (use of special oils, etc.), service can be performed at greater intervals. Also referred to as Longlife Service (VW, Audi).
WK Converter clutch
WL Warning lamp
WLR Warmup control
WR Warmup control or Warning lamp relay
WS Wiper or Travel sensor
WSA Wiper system
WSG Separate control unit
WSH Wiper lever
WSK Converter clutch used in semiautomatic transmission
WSKS Converter clutch switch
WSM Wiper motor
WSS Window screen system. A type of night-vision unit (DaimlerChrysler). Supports driver in night driving by making an infrared image of what is visible through the windscreen and displaying it on a separate screen.
WSZ AC ignition
WT Heat exchanger
WTF Water temperature sensor
WUEK Eigentlich WÜK, Wandlerüberbrückungskupplung, verhindert Schlupf im Drehmomentwandler
X X division. Diagonal division of brake circuits: one circuit for left-front and right-rear, and one circuit for right-front and left-rear.
XE Extreme economy. Selection option for extremely economical driving with automatic transmissions
XS Extreme sport. Selection option for extremely sporty driving with automatic transmissions
YRS Yaw rate sensor. Component of ESP system
YV Venezuela
Z.Z. Currently, at the moment
ZA Ignition suppression or South Africa
ZAB Central display and operating unit for information
ZAS Cylinder shutoff
ZBR Central vehicle computer
ZDA Intermediate RPM stop
ZDE Intermediate RPM adjuster
ZDR Intermediate RPM control
ZDT Cyclical nozzle-exchange procedure
ZE Central injection or Central electronics
ZEE Central injection unit, Mono-Jetronic
ZEV Zero-emissions vehicle. Vehicle producing no exhaust gases. See also LEV, NLEV, SULEV, TLEV, and ULEV.
ZGM Central gateway module
ZGW Central gateway. Computer that connects and controls data exchange between two networks
ZK Ignition circuit (airbag system)
ZKO Ignition capacitor
ZLS Auxiliary air slider
ZLV Auxiliary air valve
ZME Trim unit. Control unit for the high-pressure pump (such as CP3) of a Common Rail system. Measures the fuel quantity fed to the pump.
ZMS Two-mass flywheel
ZNPB Central delivery volume normal test stand (special tester for injection pumps)
ZOS Zero offset disc brake (no residual drag moment)
ZOT Cylinder top dead centre
ZRE Zaire
ZS Ignition coil
ZU Intermediate inspection
ZUS.LUFTP. Auxiliary air pump (secondary air injection)
ZV Central locking or Ignition distributor or Ignition timing adjustment
ZVM Central locking module
ZVN Central valve for level adjustment
ZW Between
ZWD Two-coil actuator (servomotor with two coils)
ZWG Intermediate transmission
ZWS Accessory for immobilizer
ZWV Ignition timing adjustment
ZYL Cylinder

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