Car Acronyms: What do they mean? | theAA
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Automotive acronyms

What do they mean?

Don't know your ABS from your EBD? Acronyms are now part of automotive language and they can be really confusing - even for the most dedicated motoring enthusiast. They often refer to a specific system fitted to a vehicle. To add to the confusion some car manufacturers call the same system different names!

A complete list of automotive acronyms would be virtually infinite, as with every new vehicle model comes new systems and another list of car acronyms.

We've compiled a list of the most commonly used motoring acronyms, with a brief description of what each one means. So when you go shopping for a car, you'll be armed with information to help you to understand the sales jargon.

If you're buying a new car, there are certain systems you should consider. Things like ABS, ESP, EBD etc are safety related, and many new cars will be fitted with them as standard equipment. Don't take it for granted that a new car will have them though. If they're important to you it's worth asking the question.

So, now that you are armed with some information, you can go shopping with your own list of priorities.

ABSAntilock Braking SystemPrevents the wheels of a car locking up and skidding under heavy braking so control and steering is maintained
A/CAir-conditioningAbsorbs heat and blows refrigerated air into the cabin of the car, cooling it to below the ambient air temperature
ACC Active Cruise ControlUsing a front-mounted RADAR, ACC detects slower vehicles ahead and will maintain a relative driving speed to ensure a safe following distance.
AFMActive Fuel ManagementAlso known as MDS (Multi Displacement System) or VCM (Variable Cylinder Management). During light operation the car’s engine can shut off cylinders so less fuel is used.
ATCActive Traction ControlUsed primarily in off road 4x4 applications ATC (also often referred as A-Trac) brakes spinning wheels and diverts torque to other wheels to gain traction in slippery surfaces.
AWDAll Wheel DrivePopular terminology for permanent four-wheel drive systems. Vehicle can distribute power to all four wheels rather than just to the front or rear vehicle wheels only.
BHPBrake Horse PowerThe measure of a car engine's horsepower before the rest of the vehicle's drive train. The metric equivalent is Kilowatts (kW). 1 BHP = 0.745kW.
CRDCommon Rail DieselA single, highly pressurized fuel line supplies diesel to all cylinders allowing for finer control over fuel use. Vastly reduces diesel engine's noise and improves fuel economy.
CVTConstant Velocity TransmissionA continuously variable transmission is an automatic transmission that can vary drive ratios seamlessly using an internal belt and cone arrangement.
DACDownhill Assist ControlA safety feature intended for off-road use. The vehicle's ABS and throttle control systems to maintain a gradual, more controlled decent on steep or slippery off-road surfaces.
DOHCDouble Overhead CamshaftA now very common vehicle engine design that places two camshafts (one to operate inlet valves, one to operate exhaust valves) mounted above the cylinder head.
DSGDirect Shift GearboxA computer controlled manual gearbox that pre selects additional gears to the current driven gear. No clutch pedal is required and the next gear can be engaged very rapidly.
EBDElectronic Brake DistributionElectronically controls and distributes appropriate brake pressure to all brakes dependant on load and braking force. Replaces traditional mechanical brake proportioning valve.
ECUElectronic Control UnitAn ECU is an electronic "brain" which controls a system in a car, such as the engine management system, transmission or body electrics.
EDCElectronic Damper ControlAn ECU-controlled wheel suspension system that adjusts the shock absorbers and regulates damper forces electronically adapting to changing road, load or driving conditions.
EFIElectronic Fuel InjectionEFI systems replace carburetors as fitted to older vehicles. The electronically controlled fuel injectors deliver fuel more efficiently, improving economy, emissions and drivability.
EGRExhaust Gas RecirculationA proportion of car exhaust gasses are redirected back into the car’s engine to help burn fuel more efficiently and significantly reduce harmful emissions.
ELREmergency Locking RetractorSeatbelts which are always unlocked except in emergency situations such as rapid deceleration, rapid acceleration or hard cornering vehicle manoeuvres.
ESPElectronic Stability ProgramDramatically helps in correcting vehicle instability during uncontrollable under or over steer situations by measuring lateral acceleration at the car's centre of gravity. Also Known as VSA, DSC, ESC
FSiFuel Straified InjectionAlso known as DI (Direct Injection) or GDI (Gasoline Direct Injection). Petrol is injected at high pressure directly into the car’s combustion chamber; the air fuel mixture can run far leaner than conventional EFI systems so is more efficient.
FWDFront Wheel DriveA car’s engine power is delivered through the front wheels. Is more common today than Rear Wheel Drive.
GVWGross Vehicle WeightThe maximum recommended weight for a vehicle, including: the weight of the vehicle itself, fuel and other fluids, passengers, and all cargo.
HACHill Assist ControlA safety feature intended for off-road use. Helps prevent the vehicle from rolling backward or slipping sideways when performing hill start on steep or slippery gradients.
HIDHigh Intensity DischargeHigh Intensity Discharge lighting technology uses electric inducers to provide an arc inside a gas-filled bulb, enhancing night driving. Only trained technicians should maintain the system.
kWKilowattThe metric equivalent of Brake Horsepower. Used to measure the energy output of a vehicle's engine.
LEDLight Emitting DiodeLED's are semiconductors that emit light when an electric current is applied. Increasingly popular in vehicle lighting as they have a much quicker response time and last longer.
LHDLeft Hand DriveThe steering wheel and controls on the left hand side of cars driven on the right hand side of the road in countries such as the USA.
LPGLiquid Petroleum GasLPG is a popular alternative fuel to petrol or diesel. The cost per liter is less than petrol but it is less fuel efficient.
LSDLimited Slip DifferentialA limited Slip Differential allows two driving wheels to operate in unison when one breaks traction. It provides improved control and traction in slippery conditions.
LWBLong Wheel BaseFront and rear axles are further apart therefore the body or cargo deck of a commercial vehicle will be longer than other model variations.
NMNewtonmetreMeasurement of a vehicle's engine torque. Torque is the turning force of the car’s engine.
OEMOriginal Equipment ManufacturerManufacturer/supplier of components fitted to a new car at the time of manufacture.
PASPower Assisted SteeringA system designed to reduce the effort required to steer the vehicle, particularly at low parking speeds. Can be Hydraulic, Electric or a combination of both.
PDCPark Distance ControlAn audible warning device that alerts the driver when their car is getting close to other cars or objects when parking
RHDRight Hand DriveThe steering wheel and controls on the right hand side of cars driven on the left hand side of the road in countries such as New Zealand.
RPMRevolutions Per MinuteHow fast the car’s engine is turning i.e. how many times the crankshaft rotates in one minute
RWDRear Wheel DriveA car’s engine power is delivered through the rear wheels. Less common today than FWD.
SAT-NAVSatellite Navigation SystemAlso known as GPS (Global Positioning System). GPS technology interfaces with mapping software either built to provide spoken, turn by turn instructions to drivers.
SWBShort Wheel BaseFront and rear axles are closer together therefore the body or cargo deck of a commercial vehicle will be shorter
SRSSupplementary Restraint SystemDesigned to be used in conjunction with seatbelts, SRS refers to a vehicle's airbag system. A car’s airbags are designed to reduce occupant injury in the event of a car crash and are deployed when the SRS sensors detect a predetermined level of impact force.
TDiTurbo Diesel InjectionMost modern diesel engines are now fitted with turbochargers to maximize performance.
VGTVariable Geometry TurboThis system varies airflow angle across a car engine's turbo blades providing optimum power delivery across a broader rev range. Now commonplace in modern diesel vehicle engines.
VINVehicle Identification NumberA Unique 17 digit number, for each individual car, that can indentify date of manufacture, manufacturing plant and standards etc.
VVTVariable Valve TimingVVT systems advance or retard camshaft timing to optimizing vehicle engine efficiency, performance and exhaust emissions.

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