7/31/2019 -1369321790

1/24

The term used describe a two-wheel drive vehicle. The "4"

indicates thenumber of wheels of the vehicle and the "2"

indicates the number ofwheels that are driven by engine

Four by two

4x2."4"

,"2"().

The term used describe a four-wheel drive vehicle. The first

"4"indicates the number of wheels of the vehicle and the second"4"indicates the number of wheels that are driven by engine.

Most 4x4 drivetrains have a transfer case that allows thedriver

to select either two(4x2)- or four-wheel drive (4x4) depending

ondriving conditions. In trucks, youll often find locking hubs

on thefront wheels that can be locked in the "on" or free-

wheeling position asneeded. Some performance cars have full-

time variable four-wheel driveand use a computer-controlled

transfer case to route power between thewheels

Four by four

4x4

."4""4"

The 1991-92 systems are unique in that they used 4 wheelspeed sensors(one located at each wheel) while the other

systems use the VehicleSpeed Sensor (VSS) signal for rear

wheel speed.

4Wheel Anti Lock brake

4WAL

4()

4WD is a system in which the engine's power is (or can be)transmitted to all four wheels through a two-speed transfer case

anddrive axles. The transfer case's main function is to provide a

gear-reduction feature and the ability to shift the vehicle into

four-wheel "Low" range, which is designed for severe conditions

such aspulling through heavy snow or mud, or slowly climbingup (or inchingdown) a backwoods hunting trail.

A method of driving a vehicle by applying engine torque toall

four wheels. Various schemes are used for 4WD including part-

time,full-time and variable four-wheel drive. The primaryadvantage offour-wheel drive is increased tractionwhich is

especially useful foroff-road excursions or severe weather

driving, but is of littlepractical value for normal driving.

Because of the added friction in thedrivetrain, a four-wheel

drive vehicle typically gets significantlylower fuel mileage than

a front- or rear-wheel drive vehicle.

Four-wheel drive

4WD

,transfer cas.

(/,

)..,.

Unit of measuring the electric currentAmpereA

A system that cools and dehumidifies air entering thepassengercompartment. The system uses a refrigerant to cool

the air and carryheat away from the passenger compartment.

Major system componentsinclude a compressor, condenser,

Air ConditionerA/C

7/31/2019 -1369321790

2/24

evaporator, accumulator orreceiver/dryer, and orifice tube or

expansion valve. Do not intermixdifferent types of refrigerants

in an A/C system. Use the type specifiedby the vehicle

manufacturer (R12 for most 1994 and older vehicles, orR134a

for most 1995 and newer vehicles). See also Retrofit.

AAA (the American Automobile Association, Inc.) is not-for-

profitorganization. AAA provides certain standard services to its

own members,It is providing emergency roadside assistance toits members, also AAAoperates travel agencies and publishes

maps and travel guides, and otherservices as well.

American AutomobileAssociation

AAA

().,,

,,

Active Body ControlABC

An anti-lock braking system (ABS) (translated from German,

Antiblockiersystem) is a system on motor vehicles whichprevents thewheels from locking while braking. The purpose of

this is to allow thedriver to maintain steering control under

heavy braking and, in somesituations, to shorten braking

distances (by allowing the driver to hitthe brake fully without

the fear of skidding or loss of control)Since it came intowidespread use in production cars (with "version 2"in 1978),

ABS has made considerable progress. Recent versions not onlyhandle the ABS function itself (i.e. preventing wheel locking)

but alsotraction control, brake assist, and electronic stability

control,amongst others. Not only that, but its version 8.0 systemnow weighsless than 1.5 kilograms, compared with 6.3 kg of

version 2.0 in 1978.

Antilock braking systemABS

Electric current that reverses direction periodically, usually

manytimes per second. One complete period, with current flow

first in onedirection and then in the other, is called a cycle, and

60 cycles persecond (60 hertz) is the customary frequency of

alternation in theUnited States and in all of North America. In

Europe and in many otherparts of the world, 50 Hz is the

standard frequency. On aircraft ahigher frequency, often 400

Hz, is used to make possible lighterelectrical machines

Alternating Current

AC

,.,.60(60

).(50).

400,autonomous or adaptative cruise control (ACC) systems. The

system alsogoes under the names of active cruise control (ACC)

, adaptive cruisecontrol (ACC) or intelligent cruise control

(ICC). A radar sensor islinked to the ECU which slows the

vehicle and brakes if necessary.

Adaptive Cruise Control

ACC

ACC,ICC,

,

()

()

7/31/2019 -1369321790

3/24

Advanced Driver Assistance

SystemsADAS

AFS varies the steering transmission ratio electronically in

directrelation to the style and speed of driving and road

conditions

Active front steeringAFS

Alternative fuel vehicleAFV

The automated guided vehicle or automatic guided vehicle

(AGV) is amobile robot that follows markers or wires in the

floor, or uses visionor lasers. They are most often used in

industrial applications to movematerials around a manufacturing

facility or a warehouse. Application ofthe automatic guided

vehicle has broadened during the late 20th centuryand they are

no longer restricted to industrial environments.

Automated guided vehicle

AGV

,,,

.

A unit of electrical capacity. Tells you how much power the

battery will store. Current multiplied by time in hours equals

ampere-hours. A current of one amp for one hour would be one

amp-hour; acurrent of 3 amps for 5 hours would be 15 AH

CRLF.Ampere-Hour rating: is the amount of steady current thatafully charged battery can supply for 20 hours at 26.7oC

without the cellvoltage falling below 1.75 volts or 10.5 volts at

terminals.

Ampere-Hour

AH

...11-

.3515-.-:20

26.71.7510.5.

-

AHC systems exist under many trade names, including

Electronic Height Control (EHC), Variable Ride-Height

Suspension(VRHS), and pneumatic suspension systems.Active Height Control

AHC

Air injection into the exhaust port allows the unburnt andpartially burnt fuel to be completely combusted in the exhaust

system.This system sometimes called an after-burner and itoperates when theengine is slow-running or cruising.

Air injection

AI

.

,.

Automated Manual

TransmissionAMT

Active noise control

ANC

American Petroleum

InstituteAPI

7/31/2019 -1369321790

4/24

Automatic Stability ControlASC

ASE is a nonprofit, nonaffiliated organization formed tohelp

assure the highest standards in automotive service. It directs an

organized program of self-improvement.

Automotive Service

ExcellenceASE

Also called Traction Control System (TCS.)Acceleration slip regulation

Automatic slip regulationASR (TCS)

Some vehicles can be classified as AT-PZEV, standing for

Advanced Technology PZEV. This type of vehicle is just as

clean as aPZEV vehicle, but gets much better fuel efficiency

due to the use ofhybrid electric vehicle systems. This

technology can also be used in aSport Utility Vehicle to

improve their traditionally lower fuel economy;however theymay still lag behind the efficiency of smaller vehicle

Advanced Technology-

Partial Zero Emission

VehicleAT-PZEV

-

Automatic Tire Inflation

SystemATIS

A special kind of oil for use in automatic transmissions.There

are several types: Dexron II, Dexron III, Type F, Mercon,

MerconV, Chrysler 7176 and several varieties of Chrysler ATF-

Plus. All are"friction-modified" lubricants except Type F.Dexron II and Mercon havesimilar additive packages as do

Dexron III and Mercon V. Even so, useonly the type of ATF

specified by the vehicle manufacturer. Using thewrong type of

ATF can cause transmission problems. If you do not knowwhat

type of fluid the transmission takes, READ THE OWNERS

MANUAL! Somedipsticks are also marked as to the type of

ATF required. "Universal"ATF fluids are available thatsupposedly meet the OEM requirements formany friction-

modified applications, but make sure the label says itmeets the

specific vehicle requirements before using. The newer ATFs

such as Dexron III and Mercon V are longer lived than earlier

ATFs, butcan still oxidize if the transmission runs too hot.

Trailer towing isespecially hard on ATF unless the transmission

is equipped with anauxiliary oil cooler. Recommended changeinterval for older vehicles isevery 24,000 to 30,000 miles. For

newer vehicles, see the owners manual.

Automatic transmission fluidATF

All-terrain vehicle

ATV

A vehicle (usually a car) where all four wheels are driven.Most are fulltime systems for year-round driving, and use a

viscousfluid coupling center differential instead of a transfer

case to routedrive torque to all four wheels. This allows the

front and rear wheelsto turn at slightly different speeds when

turning on dry pavement.

All wheel driveAWD

or (BAS, Brake Assist System), which automatically applies

full brakingpower when a panic stop is sensed via rapid pedalBrake AssistBA

7/31/2019 -1369321790

5/24

movement, such aswhen the driver stabs the brakes

.

()

or(BA, Brake Assist)Brake Assist SystemBAS

(

Bottom dead centerBDC

Brake horse powerBHP

Ball joint inclinationBJI

A term relating to the pressure in the cylinder calculated form

the horsepower reading on a dynamometer.Brake mean effective

pressureBMEP(bmep)

.

Brake pressure modulator valve, it is part of the anti-lock

brakes andtraction control system.Also called the Electro-Hydraulic Control Unit (EHCU). During theAntilock mode, the

BPMV can maintain or reduce brake fluid pressureindependent

of the pressure generated in the master cylinder. The BPMVdoes not provide more pressure than is applied by the master

cylinderduring braking

Brake pressure modulator

valve

BPMV

,..

,.

.

automatic transmissions are equipped with "brake transmission

systeminterlocks" to prevent children from moving the shift

mechanisms out ofpark.

Brake Transmission Shift

Interlocks

BTSI

The amount of heat required to raise 1 pound of water 1 F at

sea levelBritish thermal unit

BTU

11The crank angle sensor (CAS) is a device used in the

automobile to tell the Engine Control Unit (ECU) when to fire

the sparkplugs. The CAS detects where the piston is located in

the engine andwhen it is in the right spot it tells the ECU to fire

the spark plug inthat cylinder.The sensor is typically located on

the flywheel or on aseparate cog. One of the teeth of theflywheel is missing, the oneexactly at Top Dead Center of

cylinder #1 (the closest to the flywheel.)The sensor registers achange and responding to this, sendsout a pulse to the ECU. The

ECU is then able to calculate the injectionand ignition timing.

There are two commonly applied versions of thissensor, based

on the principle of induction and on the Hall effect. Thissensor

is the most important sensor in modern day engines. When it is

failing, the engine will not run at all

Crank Angle SensorCAS

is an automotive safety system developed by BMW. It is a

furtherdevelopment and expansion of the anti-lock braking

system, designed todistribute braking force during emergency

braking whilst cornering. CBCinteracts with ABS to counteract

oversteer and guarantees optimumdistribution of brake power in

Cornering Brake ControlCBC

7/31/2019 -1369321790

6/24

corners, keeping the vehicle heading inthe intended direction

even if the brakes are applied suddenly

Cold Cranking Amps is a rating used in the battery industry to

define abattery's ability to start an engine in cold temperatures.

The ratingis the number of amps a new, fully charged battery

can deliver at 0Farenheit for 30 seconds, while maintaining a

voltage of at least 7.2volts, for a 12 volt battery. The higher the

CCA rating, the greater thestarting power of the battery.

Cold Cranking AmpsCCA

Capacitor-discharge ignition

CDI

A family of manmade chemicals containing chlorine that

include R12automotive air conditioning refrigerant. CFCs have

been blamed for adeterioration of the Earths protective ozone

layer. CFCs have beenphased out of production by international

agreement.CFCs have beenblamed for a deterioration of the

Earths protective ozone layer.

ChlorofluorocarbonsCFCs

Center of gravity(also called Center of mass). The point in a

systemof bodies or an extended body at which the mass of the

system may beconsidered to be concentrated and at which

external forces may beconsidered to be applied.

Center of gravity

CG

().

Compression ignitionCI1

Coil ignition

CI2

Compressed natural gasCNG

A deadly gas that results from the incomplete burning of

gasolineinside the engine, carbon monoxide is considered to be

a serious airpollutant. You cant see it or smell it, but it can kill

in very smallconcentrations. Because of this you should never

run an engine inside aclosed garage. Various means are used to

reduce the amount of COproduced by an engine, and primary

among these is the catalyticconverter. The converter "reburns"

CO in the exhaust and converts itinto harmless carbon dioxide.

Carbon MonoxideCO

The amount of friction between two surfaces is expressed as a

coefficient of friction (COF). The coefficient of friction is

determinedby dividing the force required to pull an object

across a surface bythe normal force between between the two

objects.

Coefficient of frictionCOF

A type of distributorless ignition system where individual

ignitioncoils are mounted directly over each spark plug. No

spark plug wires areused.Coil-On-Plug ignition

COP

,,().

The camshaft position sensor monitors engine speed and

piston position. These input signals to the ECM are used to

control fuelinjection, ignition timing and other functions. The

Camshaft (or Crankshaft)

Position SensorCPS

7/31/2019 -1369321790

7/24

camshaft positionsensor has a rotor plate and a wave-forming

circuit. The rotor plate has360slits for a 1(POS) signal and 6

slits for a 120(REF) signal.The wave-forming circuit consistsof Light Emitting Diodes(LED) and photo diodes. The rotor

plate is positioned between the LEDand the photo diode. The

LED transmits light to the photo diode. As therotor plate turns,

the slits cut the light to generate rough-shapedpulses. These

pulses are converted into on-off signals by thewave-forming

circuit and sent to the ECM.The engine coolant temperature sensor is used to detect the

enginecoolant temperature. The sensor modifies a voltage signal

from the ECM.The modified signal returns to the ECM as theengine coolant temperatureinput. The sensor uses a thermistor

that is sensitive to the change intemperature. The electrical

resistance of the thermistor decreases astemperature increases.

Coolant temperature sensorCTS

A crossover SUV (also called CUV for Crossover Utility

Vehicle) or XUVis an automobile with a sport utility vehicle

appearance but is builtupon a more economical and fuel-efficient car-based platform.

Crossover Utility Vehicle

CUV

,.

A Constant Velocity Joint is one that provides consistent

driveshaftspeeds regardless of the operating angle of the joint.

CV joints(U-joints (Universal joints)are used primarily in onthe driveshaftsof front-wheel drive vehicles, and they come in

two basic varieties: theRzeppa ball type joints (which youll

find on the outer end of thedriveshaft) and tripod joints (which

are used on the inner end.)

Constant velocity joint

CV joint(1)

,.

,,()(

.

()

Commercial vehiclesCV(2)

()

Continuously variable transmissions (CVTs) are another

transmissiontechnology that's available in some cars. Instead of

having fixed gearratios like a conventional manual or automatic,

CVTs constantly adjustto the current driving conditions. Sincethere are no gear "steps" toshift between, CVTs often operate

more smoothly than other technologies.

Continuously variable

transmissionCVT

It is an automotive technology that allows the intake and/or

exhaustvalve timing to be infinitely varied during engine

operation.

Continuous Variable Valve

TimingCVVT

Direct currentDC

Direct Drive (transmission)DD

()Direct Fuel Injection

DFI

7/31/2019 -1369321790

8/24

Direct Ignition SystemDIS

do-it-yourself job

DIY job

An ignition system that does not use a distributor to route high

voltage to the spark plugs. The high voltage plug wire runs

directlyfrom the ignition coil to the spark plug. Some DIS

systems have one coilfor every two spark plugs (a sharedsystem), while others have aseparate coil for each spark plug

(See Coil-On-Plug Ignition.)Eliminating the distributor makesthe system more reliable andeliminates maintenance.

Distributorless Ignition

systemDLI

Also, called digital volt/ohmmeter (DVOM.)Digital multi meter

DMM

Department of Motor

VehiclesDMV

()

Cylinder Deactivation, Multiple Displacement System (MDS),

or Variable Cylinder Management.Displacement on demandDOD

The U.S. Department of EnergyDepartment of Energy

DOE

DOHC dual overhead cam engine has two camshafts in

cylinder head. Camsact directly on valves without rocker arms.

One cam operate the intakevalves the other operate the exhaust

valves.

Dual over head camDOHC

The U.S. Department of TransportationDepartment of

TransportationDOT

DOT 3 BRAKE FLUID; Brake fluid that meets the

Department ofTransportation specifications for glycol based

fluids with a wet boilingpoint (lowest allowable after its been

in use) of 284 degrees F. and adry boiling point of 401 degrees

F. DOT 3 fluid is the type commonlyspecified by most vehicle

manufacturers. Because it is glycol based, itabsorbs moisture

over time (hygroscopic). This lowers its effectiveboiling point

and promotes internal corrosion in the brake system. Forthis

reason, the brake fluid should be replaced periodically (every

twoyears is recommended by many experts) and every time thebrakes arerelined or serviced.DOT 4 BRAKE FLUID; A

"heavy-duty" glycol based brake fluidwith a slightly higher wet

boiling point of 311 degrees F. and a dryboiling point of 446

degrees. This type of fluid is sometimes specifiedfor

performance vehicles or those subject to high brake

temperatures.DOT 5 BRAKE FLUID; A silicone based fluidthat does not absorb moistureand has a boiling point of at least

500 degrees F. DOT 5 fluid does nothave to be changed

periodically and can minimize brake system corrosion,but isvery expensive compared to DOT 3 or DOT 4 fluid (it costs

threeto five times as much). It will not mix with DOT 3 or DOT4 brake fluid.DOT 5 is NOT recommended for any vehicle with

ABS brakes because ittends to aerate when cycled rapidly

through small orifices.

DOT 3, DOT

4, DOT 5

7/31/2019 -1369321790

9/24

Dynamic Stability ControlDSC

The DSG removes the clutch pedal and associated operation,

and placesit under the control of computer chips and hydraulic

servos. When leftin full auto mode, it's as smooth as or

smoother than any conventionalautomatic.

Direct Shift GearboxDSG

Computerized engine control systems have a certain amount ofbuilt-inself-diagnostic capability to detect problems that affect

engineperformance and emissions. The same is true for the

antilock brakesystem and other onboard systems that are

computer controlled. When afault is detected, the computer will

store a diagnostic trouble code inits memory and illuminate the

"Check Engine" light. On some vehicles,the computer can beput into a special diagnostic mode by groundingcertain

terminals on a diagnostic connector. This will cause the Check

Engine or other lights to flash out the fault code. On many

vehicles,though, a scan tool must be plugged into the computer

system to accessand read the codes.

Diagnostic trouble codsDTCs

()

Driving under the influenceDUI

Emergency Brake Assist (EBA) is a safety system in vehicles

designed toensure maximum braking power is used in an

Emergency stop situation. Byinterpreting the speed and pressure

at which the brake pedal is pushed,the system detects if thedriver is trying to execute an emergencystop, and if the brake

pedal is not fully applied, the system overridesand fully applies

the brakes until the Anti-lock braking system (ABS)takes overto stop the wheels locking up

Modulus of elasticityE

which automatically applies more braking power to the wheels

with thebest grip. Also called (EBFD). Often coupled with anti-

lock brakingsystems, EBD can apply more or less braking

pressure to each wheel inorder to maximize stopping power

whilst maintaining steering control.

Electronic brake-force

distributionEBD

Electronically controlled

brakesECB

or ECU electronic control unit is an embedded system that

controls one or more of the electrical subsystems in a vehicle.Electronic control module

ECM

Also called coolant temperature sensor (CTS.)Engine coolant temperature

sensorECT

or ECM electronic control module is an embedded system that

controls one or more of the electrical subsystems in a vehicle.Electronic control unit

ECU

The eCVT in the hybrid car is integral with the generator

motor. Itharnesses internal combustion and electric power

sources to drive thewheels.

Electronically controlled,

continuously variable

transmissioneCVT

7/31/2019 -1369321790

10/24

Electronic diesel control unitEDCU

EDTC prevents excessive slip of the driven wheels due to

engine dragtorque (engine brake). This may occur when driving

on slippery roadsurface if the driver change to lower gear or

suddenly lifts his footoff the throttle.

Engine drag traction controlEDTC

............. Abbreviation for Electronic Fuel Injection. This type of systemusescomputer-controlled fuel injectors to spray fuel into the

engine ratherthan mechanically controlled injectors or a

carburetor. EFI comes inseveral varieties: "throttle body

injection" (See TBI), "multi-portinjection" (See MFI or PFI) or

Sequential Fuel Injection (SFI.)Electronic fuel injection isconsidered to be superior to carburetionbecause it allows more

precise fuel metering for easier starting, loweremissions, better

fuel economy and performance.

Electronic fuel injectionEFI

The EGO sensor is mounted in the exhaust system upstream of

thecatalyst. It detects excess oxygen in the exhaust stream.

Oxygen, or thelack of it, indicates whether the air/fuel is lean or

rich of thestoichiometric ratio. The EGO sensor is also known

as a Lambda-Sondsensor or O2 sensor.

Exhaust Gas Oxygen SensorEGO

This is an emissions control technique for reducing oxides of

nitrogenemissions in the tailpipe. A small amount of exhaust gas

is recirculatedback into the intake manifold to dilute the

incoming air/fuel mixture.Contrary to what youd think, it has acooling effect on combustiontemperatures which helps reduce

the formation of oxides of nitrogen (SeeNOX). The EGR valve

is the main control device in this system.

Exhaust-gas recirculationEGR

()

EHC systems exist under many trade names, including

VariableRide-Height Suspension (VRHS), Active Height

Control (AHC), andpneumatic suspension systems.Electronic Height Control

EHC

Electro-hydraulic power

steeringEHPS

Electronic IgnitionEI

Pure brake by wire, no brake fluid, no brake lines, electric

motorgenerates braking force, and wheel brake ECU actuated

from electronicbrake pedal

Electro Mechanical BrakeEMB

In an Engine Management System (EMS), electronics control

fueldelivery, ignition timing and firing order. Primary sensors

on thesystem are engine angle (crank or Top Dead Center

(TDC) position,)airflow into the engine and throttle demandposition. The circuitrydetermines which cylinder needs fuel and

how much, opens the requisiteinjector to deliver it, then causes a

spark at the right moment to burnit. Early EMS systems usedanalogue computer circuit designs toaccomplish this, but as

embedded systems became fast enough to keep upwith the

Engine Management SystemEMS

7/31/2019 -1369321790

11/24

changing inputs at high revolutions, digital systems started to

appear.

Abbreviation for the Environmental Protection Agency, the

governmentagency responsible for enforcing anti-pollution

rules. The EPA requiresall vehicle manufacturers to certify their

new car as being incompliance with the applicable clean air

standards for the year ofmanufacture. The manufacturer, in turn,

must provide an "emissions"warranty on every vehicle they sellthat guarantees free replacement ofany emissions control device

that might fail during that time. Thiscoverage usually extends to

such items as the computer control system,catalytic converter,fuel and ignition system (except the spark plugsand normal wear

items.)

Environmental ProtectionAgencyEPA

Evaporator pressure

regulatorEPR

Electronic power steeringEPS

ESC systems exist under many trade names, including Vehicle

StabilityControl (VSC), Electronic Stability Program (ESP), and

Vehicle StabilityEnhancement (VSE.)Electronic Stability Control

ESC

ESP systems exist under many trade names, including Vehicle

StabilityControl (VSC), Electronic Stability Control (ESC), and

Vehicle StabilityEnhancement (VSE.)Electronic stability program

ESP

Electronic throttle control

ETC(1)

The Electronic Transmission is an automatic transmission

which uses modern electronic control technologies to control the

transmission. The transmission itself, except for the valve body

andspeed sensor, is virtually the same as a full hydraulically

controlledtransmission, but it also consists of electronic control

unit andactuators.The electronic sensors monitor the speed ofthe vehicle,gear position and throttle opening, sending this

information to the ECU.The ECU then controls the operation ofthe clutches and brakes based onthis data and controls the

timing of shift points and torque convertertock-up.

Electronic Traction ControlETC(2)

Electronic transmission

control unitETCU

Emergency tensioning

deviceETD

Electric vehicle

EV

Electronic Wedge Brake

EWB

Free body diagramFBD

Fuel cell vehicle

FCV

7/31/2019 -1369321790

12/24

Forward Collision WarningFCW

Flexible fuel vehicles (FFVs) are designed to run on gasoline

or ablend of up to 85% ethanol (E85). Except for a few engine

and fuelsystem modifications, they are identical to gasoline-only

models.

Flexible-fuel vehicleFFV

fixed geometry intake manifold.fixed geometry intakemanifold.FGI

Federal Motor Vehicle

Safety StandardsFMVSS

A means of driving a vehicle by applying engine power to the

frontwheels instead of the rear wheels. There are advantages and

disadvantages to front-wheel drive. On the plus side, the

advantages gomostly to the vehicle manufacturers because it

makes it easier for themto package a vehicle

engine/drivetrain/body combination moreefficiently. In other

words, the same basic engine/drivetrain packagecan be installedunder a variety of "different" model cars. The samebasic

engine/transaxle package Chrysler developed for their Omni and

Horizon (which they basically copied from Volkswagen) can be

found underall their current front-wheel drives ranging from the

mini-vans to thesports sedans. Thus a manufacturer can save a

bundle in tooling anddevelopment when he wants to bring a new

front-wheel drive model to theshowroom floor. As far as FWD

being superior to RWD, its mostly hype.Some people willargue that front-wheel drive handles better thanrear-wheel drive

while others will argue exactly the opposite. Porscheand

Mercedes seem to be unimpressed by FWD, and most race carsarerear-wheel drive. On the negative side, some front-wheel

drive cars havea tendency to "torque steer" (See Torque Steer),

and transaxle problemscan be very costly to repair because it

often involves pulling theengine.

Front wheel driveFWD

The shear modulus or modulus of rigidity (G or ) describes an

object'stendency to shear (the deformation of shape at constant

volume) whenacted upon by opposing forces; it is defined as

shear stress over shearstrain. The shear modulus is partof the

derivation of viscosity.

Modulus of rigidityG

gram per milegpm

The Global Positioning System (GPS) is a global navigation

satellitesystem (GNSS) developed by the United States

Department of Defense andmanaged by the United States Air

Force 50th Space Wing. It is the onlyfully functional GNSS in

the world, can be used freely, and is oftenused by civilians for

navigation purposes. It uses a constellation ofbetween 24 and 32

medium Earth orbit satellites that transmit preciseradiowave

signals, which allow GPS receivers to determine their current

location, the time, and their velocity. Its official name isNAVSTARGPS. Although NAVSTAR is not an acronym, a few

backronyms have beencreated for it.Since it became fullyoperational in 1993, GPS has become a widely usedaid to

Global positioning systemGPS

7/31/2019 -1369321790

13/24

navigation worldwide, and a useful tool for map-making, land

surveying, commerce, scientific uses.

Abbreviation for gross vehicle weight. GVW is the weight of

the vehicleplus the weight of all passengers and cargo up to the

limit specifiedby the manufacturer

Gross vehicle weightGVW

is the maximum allowable total weight of a road vehicle ortrailer thatis loaded, including the weight of the vehicle itself

plus fuel,passengers, cargo, and trailer tongue weight.Gross vehicle weight rating

GVWR

Acronym for "Heating, Ventilation and Air ConditioningHeating, Ventilation and Air

ConditioningHVAC

,,

A hydrocarbon (HC) is any kind of substance that contains

hydrogen andcarbon. Gasoline is a hydrocarbon. So is oil. When

gasoline burns insidean engine, there is always a tiny amountthats left over. If an engineis misfiring because of a fouled

spark plug or a leaky valve, or if ithas worn rings or valveguides and uses oil, quite a bit of unburned HCcan pass through

into the exhaust. Unburned HC is a major source of airpollution

and is the primary source of smog in most urban areas. Various

means are used to reduce the amount of HC an engine produces,

theprimary one of which is the catalytic converter. The

converter reducesHC emissions by "reburning" and converting

it into harmless water vapor

Hydro carbonHC

is a form of internal combustion in which well-mixed fuel and

oxidizer(typically air) are compressed to the point of auto-ignition.

Homogeneous charge

compression ignitionHCCI

Hybrid electric vehicle

HEV

The HO2S is placed into the exhaust manifold. It detects the

amount ofoxygen in the exhaust gas compared to the outside air.

The sensor has aclosed-end tube made of ceramic zirconia. The

zirconia generates voltagefrom approximately 1V in richer

conditions to 0V in leaner conditions.The sensor signal is sent tothe ECM. The ECM adjusts the injectionpulse duration to

achieve the ideal air-fuel ratio. The ideal air-fuelratio occursnear the radical change from 1V to 0V.

Heated Oxygen SensorHO2S

Hydraulic Power Steering

HPS

Headway Monitoring

HWM

Highway

hwy

Symbol of electric currentElectric current

I

Intake air temperature sensor. Also has a verity if names inthepast (ACT, VAT, MCT, MAT and ATS) under OBD II

guidelines, theseparts are now called IATs.The intake airtemperature sensor is mounted to the air ducthousing. The

Intake air temperatureIAT

7/31/2019 -1369321790

14/24

sensor detects intake air temperature and transmits asignal to the

ECM. The temperature-sensing unit uses a thermistor thatis

sensitive to the change in temperature. Electrical resistance of

thethermistor decreases in response to the temperature rise

Integrated circuit

IC

Also named Adaptive Cruise Control(ACC)Intelligent Cruise ControlICC

()

Internal combustion engineICE

Independent Front

SuspensionIFS

Insurance Institute for

Highway SafetyIIHS

Independent RearSuspensionIRS

Idle Speed Control system

ISC

Integrated Starter/Generator

ISG

/

Idle Speed Control ValveISCV

Energy unit (1Joule = 1 Newton meter)Joule

J

(1=1)

kilo = 1000KiloK

1=1000The bulk modulus (K) describes volumetric elasticity, or the

tendencyof an object's volume to deform when under pressure;

it is defined asvolumetric stress over volumetric strain, and is

the inverse ofcompressibility. The bulk modulus is an extension

of Young's modulus tothree dimensions

Bulk modulusK

Toyota also demonstrated its Kinetic Dynamic Suspension

System (KDSS). By allowing the decoupling of thefront and

rearstabilizer bars, KDSS allows greater suspension articulation

(movement,that is) off-road.The KDSS-assisted truck was ableto keep all its tires incontact with the ground due to the greater

suspension travel afforded bythe system, while the one with

KDSS switched off has a rear tireclawing at thin air.Anotherbenefit of KDSS is that it allows larger stabilizerbars for

improved on-road handling via decreased body roll.

Kinetic Dynamic Suspension

SystemKDSS

The angle formed by a line that runs through the king pin in

the steering knuckle on a truck with an I-Beam axle. Its the

same asthe steering axis inclination (SAI.)

King pin inclinationKPI

The knock sensor is mounted on the engine block. It detects

the vibration caused by detonation.Knock sensor

KS

7/31/2019 -1369321790

15/24

A liter is a metric unit of measure for volume. One liter is

equal to one thousand milliliters cube.Liter

l.1000

.Left

L

A "Liquid Crystal Display" is a type of electronic display that

formsopaque or dull-colored letters or numbers on variousbackgrounds. LCDdisplays are popular for digital dashboards,

but they are not asreadable in direct sunlight as LED displays

Liquid crystal displayLCD

Lain Departure Warning

LDW

()

A light emitting diode emits light when current is passed

through it in the forward direction.A "Light Emitting Diode" isan electronic light bulb ofsorts that produces colored light.

Youll find LEDs used in the centerhigh mounted stop light on

many vehicles, and used as indicator lightsin some

instrumentation. LEDs are also used in some vehicle speedsensors and in some electronic ignitions.

Light emitting diode

LED

Low emission vehicleLEV

Liquefied natural gas

LNG

Liquefied petroleum gas

LPG

Limited-slip differentialLSD

Length unitmeterm

Tire rating for mud and snowM+S, MS, M/S or M and SMud and snow

M+S

The mass airflow sensor is placed in the stream of intake air. It

measures the intake flow rate by measuring a part of the entire

intakeflow. It consists of a hot wire that is supplied with electric

currentfrom the ECM. The temperature of the hot wire is

controlled by the ECM acertain amount. The heat generated by

the hot wire is reduced as theintake air flows around it. Themore air, the greater the heat loss.Therefore, the ECM must

supply more electric current to maintain thetemperature of the

hot wire as airflow increases. The ECM detects theairflow by

means of this current change.

MassAir flow sensorMAF

A fuel injection system that opens its injectors in pairs or

groups a sufficient amount of time prior to intake valve opening

so theintake port is filled with fuel before the valve opens.TheManifold Absolute Pressure sensor measures changes inthe

intake manifold pressure resulting from engine load and speedchanges. The computer sends a 5-volt reference signal to the

MAP sensor.As pressure changes in the intake manifold occur,the electricalresistance of the MAP sensor also changes. By

monitoring the sensoroutput voltage, the computer can

Manifold absolute pressure

(sensor)MAP

7/31/2019 -1369321790

16/24

determine the manifold absolutepressure. The higher the MAP

voltage output the lower the engine vacuum,which requiresmore fuel. The lower the MAP voltage output the higherthe

engine vacuum, which requires less fuel. Under certain

conditions,the MAP sensor is also used to measure barometricpressure. This allowsthe computer to automatically adjust for

different altitudes. Thecomputer uses the MAP sensor to control

fuel delivery and ignitiontiming.

Cylinder Deactivation, DisplacementOn Demand (DOD), or

Variable Cylinder Management.Multiple Displacement

SystemMDS

Mechanical Efficiency

ME

Abbreviation for Multi-port Fuel Injection, a type of fuel

injectionsystem that has one injector for each engine cylinder.

Each injectorsprays its fuel directly into the intake port in the

cylinder head.Multi-port fuel injection is considered to be the

"hot" setup because itprovides better cylinder-to-cylinder fueldistribution for more power.

Multi-port Fuel InjectionMFI (MPI)

Abbreviation for Miles Per Gallon. A vehicles fuel economy

isdetermined by a number of factors including the size of the

engine, thetype of carburetion used, the weight of the vehicle,

the type oftransmission used (manual or automatic), the final

drive ratio, the sizeand type of tires used, tire inflation

pressures, aerodynamicstreamlining of the body, the driving

habits of the driver, the kind ofroad surface and terrain upon

which the vehicle is driven, the speed atwhich its driven, and

environmental factors such as temperature, windand humidity.Taking all these into consideration, its no wonder theEPA says

"the mileage you get may vary from the official EPA estimates".

Mile per gallonMPG (mpg)

Multiport fuel injection

MPI (MFI)

Multi-purpose vehicleMPV

Unit of measuring force (1 Newton = 1 kg m/s.s)Newton

N(1=1/.)

NeutralN

The North American Automobile Trade Association (NAATA)

is anot-for-profit association of vehicle dealers that buy and sell

vehiclesacross international borders.

The North American

Automobile Trade

AssociationNAATA

.

No cause for removalNCFR

Abbreviation for the National Highway Traffic and Safety

Administration. This is the government agency that is

responsible formaking and policing safety rules for all vehicles.

NHTSA is the agencythat can order a vehicle manufacturer to

issue a safety recall.

National Highway TrafficSafety AdministrationNHTSA

7/31/2019 -1369321790

17/24

National Transportation

Safety BoardNTSB

Noise, vibration and

harshnessNVH

,,

OxygenO2

On board diagnostics

OBD

On board diagnostics II

OBD II ,1996.

()

Outside diameterO.D.

Over Drive (transmission)

OD

()Original equipment

OE

Original equipment

manufacturerOEM

In an overhead cam engine (OHC), the camshaft is located in

the top ofthe cylinder head. Push rods are NOT needed to

operate the rockers andvalves. With the cam in head , the

number of valve train parts isreduced. Also the valves can

placed at an angle to improve breathing.The OHC increase highspeed efficiency and power output. The OHC can besingle

overhead cam SOHC, or dual overhead cam DOHC.

Over head camOHC

The unit of electrical resistance measurement. One ohm is the

resistance that will allow one ampere to flow when pushed by

one volt.(Resistance measuring unit)

ohm

()

Engines with the camshaft in the block are called Overhead

Valve (OHV) Engines.Over head valve

OHV ,(),

.

An off-road vehicle is considered to be any type of vehicle

which is capable of driving off paved or gravel surface.Off-Road Vehicle

ORV

Unit of pressure (1 Pa = 1 N/m2), (1 MPa = 1000,000 Pa = 1

N/mm2)Pascal

Pa(1=1/),(1=1000,000

=1/)PCM is a computer that manages engine and power train

systems. Withinengine management, the PCM is responsible forfuel delivery, ignitiontiming and some emission control devices.

Power control module

Powertrain control modulePCM

Positive crank casePCV

7/31/2019 -1369321790

18/24

ventilation

Port fuel injection

PFI

Plug-in Hybrid Electric

VehiclePHEV

This unit reduces the air pressure supply to the front axle of the

towing vehicle is de-coupled in order to reduce the braking

power andmaintain vehicle stability of the now much lighter

vehicle.

Pressure limiting valvePLV

Measure of air pollution. It is common practice to express the

quantity of a gaseous pollutant in the air as parts per million.Parts per million

ppm

()

Power split devicePSD

Pound per square inch

PSI (psi)

The power steering oil pressure switch is attached to the power

steering high-pressure tube and detects a power steering load.

When apower steering load is detected, it signals the ECM. The

ECM adjusts theidle speed for the increased load.

Power Steering Pressure

SwitchPSPS

photovoltaic

PV

Partial Zero Emission

VehcilePZEV

Symbol of electric chargeQuantity of electric charge

Q

RadialR(1)

Reverse

R(2)

RightR(3)

Ford's RABS or GM and DaimlerChrysler's RWAL; control

both rear wheels at the same time.Rear Anti-Lock Brake

SystemRABS

The microprocessor can both read and write data to each

memory location.Random access memory

RAM

RAV

RC is the number of minutes a fully charged battery at 80

degrees F(26.7degrees C) can be discharged at 25 amps until

the voltage fallsbelow 10.5 volts.

Reserve Capacity

RC

Remotely controlled racing carsRemotely Controlled

RC, R/C

7/31/2019 -1369321790

19/24

Run Flat TireRFT

Read only memory

ROM

Revolutions per minute

RPM (rpm)

Recreational VehicleRV

() GM and DaimlerChrysler's RWAL or Ford's RABS; controlboth rear wheels at the same time.

Rear Wheel Anti Lock brake

systemRWAL

Rear wheel driveRWD

SAE International (SAE) is a professional organization for

mobilityengineering professionals in the aerospace, automotive,

and commercialvehicle industries. The Society is a standards

development organizationfor the engineering of powered

vehicles of all kinds, including cars,trucks, boats, aircraft, andothers. Membership is open to the publicfor those particularly

interested in Human Factors and ErgonomicStandards.

Society of Automotive

EngineeringSAE

Is the amount that the spindle support arm leans in the top. SAI

isalso known as ball joint inclination BJI or king pin inclination

KPI

Steering axis inclinationSAI

()

Sensotronic Brake ControlSBC

Steer-by-wireSBW

Specific fuel consumption is equal to the mass rate of the fuel

consumption divided by the engine brake powerSpecific Fuel Consumption

SFC

Sequential fuel injectors

SFI

Spark Ignition

SI-1

SI-2

Spark Ignition DirectInjection

SIDI

Short-long arm suspension systemShort-long arm

SLA

The Sequential Manual Gearbox enables sporty, rapid gear

changesthrough all six gears via the steering wheel paddles or

selector lever,without the use of a clutch. Select Dynamic

Driving Control (Sportbutton) for faster engine response andeven more spontaneous drivingenjoyment.

Sequential Manual GearboxSMG

SOHC single overhead cam engine has one camshaft in

cylinder head, Cam act directly on valves or rocker arms can beSingle over head camSOHC

7/31/2019 -1369321790

20/24

used.

SRS means supplemental restraint system, and airbags fall into

thatcategory. So when you get in the new car and you see theletters SRSon your steering wheel, that's what it means. It

means you have airbagsin the car. Could be front impact airbags

that just come out of yoursteering wheel in the dashboard on the

passenger side. Newer cars haveairbags throughout the car. Side

curtain airbags, thorax airbags, frontairbags, back airbags.

Supplemental Restraint

SystemSRS

It is the calculation of a vehicle, at rest,rollover resistanceSSF

= T / 2 Hwhere, T is the "track width" of the vehicle and H is

the "height of center of center if gravity" of the vehicle.Thelower the SSF number, the more likely the vehicle is to rollover

in a "single-vehicle crash"

Static Stability FactorSSF

Special Service Tools

SST

Sport utility vehicleSUV

Carbureted and throttle-body injection engines have heated air

controls in the air cleaner. This is called a TAC.Thermal Air Cleaner

TAC

()

Most electronic automatic transmissions utilize a TCC

solenoid to lockthe torque converter electronically. Once

locked, the torque converterno longer applies torque

multiplication and will spin at the same speedas the engine

(assuming the converter is fully locked.)

Torque Converter Clutch

SolenoidTCC

Traction control system prevents wheels from spinning in

slipperyconditions by automatically cutting engine power,

lightly applying thebrakes or both.Traction control system

TCS(ASR)

Also ATDS , BTDC (after top dead center, before top dead

center)Top dead center

TDC

Thermal Efficiency

TE

This systemlet you know when you need to add air to your

tires. Thesesystems don't warn you until your tire has lost 25%of its pressure,the point at which danger may loom.

Tire pressure monitoringsystemTPMS

The throttle position sensor responds to the accelerator pedal

movement. This sensor is a kind of potentiometer that transforms

thethrottle position into output voltage, and emits the voltage

signal tothe ECM. In addition, the sensor detects the opening

and closing speedof the throttle valve and feeds the voltage

signal to the ECM. The ECMreceiving the signal from the

throttle position sensor determines idleposition of the throttle

valve. This sensor controls engine operationsuch as fuel cut. On

the other hand, the "Wide open and closed throttleposition

switch", which is built into the throttle position sensor unit,isnot used for engine control.

Throttle position sensorTPS

7/31/2019 -1369321790

21/24

Technical Service BulletinsTSB

This may also be known as an input speed sensor (ISS). This

sensorsends a varying frequency signal to the Transmission

Control Unit todetermine the current shaft speed of the input

shaft or torqueconverter. The Transmission Control Unit uses

this shaft speed todetermine slippage across the torque converter

and potentially todetermine the rate of slippage across the bands

and clutches.

Turbine Speed SensorTSS

The manifold heat control valve routs exhaust gas under the

floor ofthe intake manifold when the engine is cold. This is

improves thevaporization of the cold fuel. This is also called an

early fuelevaporation (EFE) vlave.

Thermal Vacuum SwitchTVS

()(Pollution control system) Also called PVS ported vacuum

switch. Thisprevents vacuum from operating the EGR valve

before the engine is wormedup.Thermal Vacuum Valve

TVV

Universal jointU-joint

()

This grading system, allows consumers to compare tire

treadwear,traction performance, and temperature resistance. Thefederal governmentrequires tire manufacturers to grade their

tires in these three areasand place the information on the

sidewall of the tire.

Uniform Tire Quality

Grading Uniform Tire

Quality Grading SystemUTQG

UTQGS

Unit of measuring electric potentialVoltV

Vehicle-to-grid (V2G) describes a system in which power can

be sold tothe electrical power grid by an electric-drive motor

vehicle that isconnected to the grid when it is not in use for

transportation.Alternatively, when the car batteries need to befully charged, the flowcan be reversed and electricity can be

drawn from the electrical powergrid to charge the battery.

Vehicle-to-gridV2G

Variable compression ratio is the technology to adjust internal

combustion engine cylinder compression. This is done toincrease fuelefficiency while under varying loads. Higher loads

require lower ratiosto be more efficient and vice versa. Variable

compression engines allowfor the volume above the piston at

'Top dead centre' to be changed. Thisneeds to be done

dynamically in response to the load and drivingdemands.

Variable Compression Ratio

EnginesVCR

Volumetric efficiency is the ratio of the volume of air drawn

into a cylinder to the piston displacement.Volumetric Efficiency

VE()()

().()

VDIM, Toyota's new system optimizes vehicle control by

adding newfeatureselectronically controlled brakes (ECB)

and electronic powersteering (EPS) and having them work in

concert with the stabilitycontrol (VSC), ABS, EBD and BA

Vehicle dynamic integrated

managementVDIM

7/31/2019 -1369321790

22/24

systems. Faster processing speed alsopromises more transparent

operation of the system.

Vehicle dynamic integrated

systemVDIS

Variable Geometry Intake

(manifold)VGI

The steering gear ratio will be changed in accordance with

vehicle speedVariable gear ratio steering

VGRS (1)

Variable gear ratio systemVGRS (2)

Vehicle identification

numberVIN

()

VRHS systems exist under many trade names, includingElectronic HeightControl (EHC), Active Height Control (AHC),

and pneumatic suspensionsystems. Depending on conditions

such as vehicle speed and terrain,Variable Ride-HeightSuspension (VRHS) raises or lowers the ride heightof the

vehicle while it is in motion. Some VRHS systems operate

automatically, while others require the driver to select the

appropriatemode. VRHS systems can have a favorable effect on

a vehicle'slikelihood to roll over because they lower the height

of the vehicle'scenter of gravity and improve its Static Stability

Factor (SSF) ratingfor highway driving.

Variable Ride-Height

SuspensionVRHS

Vehicle stability assist

VSA

The VSC is the brains of the hybrid car. It helps to manage

charging,drive assist, and engine starting functions. It shuts theengine downduring coasting and at stoplight to save fuel. It also

converts thetraction motor into a generator during braking to

help recharging thebatteries.

Vehicle system controlVSC (1)

VSC systems exist under many trade names, including

ElectronicStability Program (ESP), Electronic Stability Control(ESC), and VehicleStability Enhancement (VSE.)

Vehicle stability controlVSC (2)

ESP systems exist under many trade names, including Vehicle

StabilityControl (VSC), Electronic Stability Control (ESC), and

Vehicle StabilityEnhancement (VSE.)

Vehicle Stability

EnhancementVSC

The vehicle speed sensor is installed in the transaxle. It

contains apulse generator that provides a vehicle speed signal to

the speedometer.The speedometer then sends a signal to theECM

Vehicle speed sensorVSS

It is a valve train system developed by Honda to improve the

volumetricefficiency of a four-stroke internal combustion

engine. This systemuses two camshaft profiles and

Variable Valve Timing and

Lift Electronic ControlVTEC

7/31/2019 -1369321790

23/24

electronically selects between theprofiles. This was the first

system of its kind. Different types ofvariable valve timing and

lift control systems have also been producedby other

manufacturers (MIVEC from Mitsubishi, VVTL-i from Toyota,VarioCam Plus from Porsche, VVL from Nissan, etc). It was

invented byHonda R and D engineer Ikuo Kajitani. It can be

said that VTEC, theoriginal Honda variable valve control

system, originated from REV(Revolution-modulated valvecontrol) introduced on the CBR400 in 1983known as HYPER

VTEC

.

.

Variable Valve Actuation

SystemsVVA

Valve timing is adjusted on intake, and valves and there is theDualVVT-i engine, Valve timing is adjusted on both intake and

exhaust valves

Variable Valve TimingVVT

Variable Valve Timing with

intelligenceVVT-i

Variable Valve Timing and

Lift - IntelligentVVTL-i

Unit of power (1 W = 1 kg m/s), (1 W = 1 J/s)WattW

(1=1/)Wide open throttle (WOT) refers to an internal combustion

engine'smaximum intake of air and fuel that occurs when the

throttle platesinside the carburetor or throttle body are "wide

open", providing theleast resistance to the incoming air. In the

case of an automobile, WOTis when the accelerator is depressed

fully.

Wide Open Throttle

WOT

/

.().

Wheel speed sensorWSS

XUV: A crossover SUV (also called CUV for Crossover

Utility Vehicle) isan automobile with a sport utility vehicle

appearance but is built upona more economical and fuel-

efficient car-based platform.

Crossover Utility VehicleXUV

YZero emission vehicle

ZEV

7/31/2019 -1369321790

24/24

Symbols

g gravity

g

h height

h

l length, liter

l ,

m massm

p pressure

p

P power

P

t time

t

T torque

T

v velocityv

V volum

V

w weight

w

coefficient of friction

angular speed

pi

radius, density

stress strain

summation

, angle

sheer stress

efficiency

delta