The glossary is a list of technical terms or acronyms and their definitions. It is not intended to be a dictionary of components and their functions. If a detailed description of a specific component is desired, refer to the related Service Manual Group.

A/C:Air Conditioning.

A/T:Automatic Transmission/Transaxle.

ABS:Anti-lock Brake System.

Absolute Pressure:The pressure referenced to a perfect vacuum.

ACC:Air Conditioning Clutch.

ACCS:Air Conditioning Cycling Switch.

ACD:Air Conditioning Demand.

ACON:Air Conditioning On.

ACP:Air Conditioning Pressure.

ACPSW:Air Conditioning Pressure Switch.

Actuator:A mechanism for moving or controlling something indirectly instead of by hand.

Air Conditioning (A/C):A vehicular accessory system that modifies the passenger compartment air by cooling and drying the air.

Air Conditioning Clutch (ACC):Indicates status of the A/C clutch.

Air Conditioning Cycling Switch (ACCS):Indicates status of the A/C cycling switch.

Air Conditioning Demand (ACD):Indicates status of the A/C demand switch.

Air Conditioning On (ACON):Indicates status of the A/C system.

Air Conditioning Pressure (ACP):Indicates pressure in the A/C system.

Air Conditioning Pressure Switch (ACPSW):A switch used for additional A/C system pressure control. Also referred to as the refrigerant containment/fan function switch.

AIR:Secondary Air Injection.

AIRB:Secondary Air Injection Bypass.

AIRD:Secondary Air Injection Diverter.

Ambient Temperature:Temperature of the air surrounding an object.

Anti-lock Brake System (ABS):Prevents wheel lockup during an emergency stop by modulating brake pressure. Allows the driver to maintain steering control and stop the vehicle in the shortest possible distance under most conditions.

AODE:Automatic Overdrive Electronic transmission.

ARC:Automatic Ride Control.

ATDC:After Top Dead Center.

Automatic Ride Control (ARC):A system that automatically adjusts the suspension system to accommodate varying road and driving conditions.

AX4N:Automatic 4 speed Non-synchronous transaxle.

AX4S:Automatic 4-speed Synchronous transaxle.

B+:Battery Positive Voltage.

BARO:Barometric Pressure.

Barometric Pressure (BARO):The pressure of the surrounding air at any given temperature and altitude.

Base Idle:Idle rpm determined by the throttle lever hardset on the throttle body with the IAC solenoid disconnected.

Base Timing:Spark advance in degrees before top dead center of the base engine without any control from the PCM or ICM.

Battery:An electrical storage device designed to produce a DC voltage by means of an electrochemical reaction.

Battery Positive Voltage (B+):The positive voltage from the battery or any circuit connected directly to the battery. Compare "Vehicle Power (VPWR)."

Blower (BLR):A device designed to supply a current of air at a moderate pressure. A blower usually consists of an impeller assembly, a motor and a suitable case. The blower case is designed as part of the ventilation system.

BLR:Blower.

BOO:Brake On/Off.

BPA:Bypass Air.

Brake On/Off (BOO):Indicates the position of the brake pedal.

Breakout Box:A service tool that "tees" between the PCM and the 104-pin harness connector. The breakout box contains test pins that can be probed for EEC system testing.

BTDC:Before Top Dead Center.

Bus+ or -:Bus positive or negative.

Bus positive or negative (Bus+ or -):Circuits that carry data to the DLC from the various modules.

Bypass Air (BPA):Mechanical control of throttle bypass air.

Camshaft:A shaft on which phased cams are mounted. The camshaft is used to regulate the opening and closing of the intake and exhaust valves.

Camshaft Position (CMP):Indicates camshaft position.

Canister:A device designed to hold dry material. An evaporative emission canister contains activated charcoal which absorbs fuel vapors and holds them until the vapors can be purged at an appropriate time.

Canister Purge:Controls purging of the EVAP canister.

Canister Vent (CV):Release of fuel vapor from the carbon canister to the atmosphere.

Case Ground (CSE GND):PCM case ground.

Catalytic Convertor:An in-line, exhaust system device used to reduce the level of engine exhaust emissions.

CCD:Computer Controlled Dwell.

CCRM:Constant Control Relay Module.

CCS:Coast Clutch Solenoid.

CD4E:CD class vehicle, 4 speed, Electronic transmission.

CHT:Cylinder Head Temperature.

CID:Cylinder Identification.

Circuit:A complete electrical path or channel, usually includes the source of electrical energy. Circuit may also describe the electrical path between two or more components. May also be used with fluids, air or liquids.

CKP:Crankshaft Position.

Clutch:A mechanical device which uses mechanical, magnetic or friction type connections to facilitate engaging or disengaging of two shafts or rotating members.

Clutch Pedal Position (CPP):Indicates clutch pedal position.

CMP:Camshaft Position.

CO:Carbon Monoxide.

CO ₂:Carbon Dioxide.

Coast Clutch Solenoid (CCS):Controls the application and release of the coast clutch in the transmission.

Coil:A device consisting of windings of conductors around an iron core, designed to increase the voltage and for use in a spark ignition system.

Computed Timing:The total spark advance in degrees before top dead center. Equals base timing plus/minus an additional factor calculated by the PCM based on input from a number of sensors.

Constant Control Relay Module (CCRM):A relay module that provides on-off control of various EEC components.

Continuous Memory:The portion of KAM used to store DTCs generated during Continuous Memory Self-Test.

Continuous Memory Self-Test:A continuous test of the EEC system conducted by the PCM whenever the vehicle is operating.

Control:A means or a device to direct and regulate a process or guide the operation of a machine, apparatus or system.

Coolant:A fluid used for heat transfer. Coolants usually contain additives such as rust inhibitors and antifreeze.

CPP:Clutch Pedal Position.

Crankshaft:The part of an engine which converts the reciprocating motion of the pistons to rotary motion.

Crankshaft Position (CKP):Indicates crankshaft position.

CSE GND:Case Ground.

Curb Idle:PCM controlled idle rpm.

CV:Canister Vent.

Cylinder Head Temperature:The temperature of the engine cylinder head.

Cylinder Identification (CID):Provides crankshaft or camshaft position information for fuel injection synchronization.

Data:General term for information, usually represented by numbers, letters, or symbols.

Data Link Connector (DLC):Connector providing access and/or control of the vehicle information, operating conditions, and diagnostic information.

Data Output Line (DOL):A circuit that sends certain information from the PCM to the instrument cluster.

Data Positive or Negative (DATA+ or DATA-):Circuits that carry data to the DLC, Message Center, or VCRM.

DATA+ or DATA-:Data Positive or Negative.

Daytime Running Lamps (DRL):A system that keeps the vehicle running lamps on at all times while the vehicle is operating.

DEF:Defroster.

Defroster (DEF):An electrically heated device designed to remove ice, frost or snow from the rear window of the vehicle.

DI:Distributor Ignition.

Diagnostic Test Mode (DTM):A level of capability in an On-Board Diagnostic (OBD) system. This may include different functional states to observe signals, a base level to read Diagnostic Trouble Codes, a monitor level which includes information on signal levels, bi-directional control with on/off board aids, and the ability to interface with remote diagnosis.

Diagnostic Trouble Code (DTC):An alpha/numeric identifier for a fault condition identified by the On-Board Diagnostic System.

Differential Pressure:The pressure difference between two regions, such as between the intake manifold and the atmospheric pressures.

Differential Pressure Feedback EGR:An EGR system that monitors differential EGR pressure across a remote orifice to control EGR flow.

Distributor:A mechanical device designed to switch a high voltage secondary circuit from an ignition coil to spark plugs in the proper firing sequence.

Distributor Ignition (DI):A system in which the ignition coil secondary circuit is switched by a distributor in proper sequence to various spark plugs.

DLC:Data Link Connector.

DOHC:Dual Overhead Cam.

DOL:Data Output Line.

DRL:Daytime Running Lamps.

DTC:Diagnostic Trouble Code.

DTM:Diagnostic Test Mode.

Dual Overhead Cam (DOHC):An engine configuration that uses two camshafts positioned above the valves.

DVOM:Digital Volt-Ohm Meter.

E4OD:Electronic 4-speed Overdrive transmission.

EAIR:Electric Secondary Air Injection.

EAP:Electric Air Pump.

ECT:Engine Coolant Temperature.

EEC:Electronic Engine Control.

EEC-V:Ford's fifth generation EEC system.

EFT:Engine fuel temperature.

EGR:Exhaust Gas Recirculation.

EGR Vacuum Regulator:Controls EGR flow by changing vacuum to the EGR valve.

EI:Electronic Ignition.

Electric Air Pump (EAP):An electric pump used in EAIR systems.

Electronic Engine Control (EEC):The system that provides electronic control of engine operation.

Electronic Ignition (EI):A system in which the ignition coil secondary circuit is dedicated to specific spark plugs without the use of a distributor. Ford has two types of EI systems, integrated EI and EI. EI is only used on the 3.0L Windstar and has a standalone Ignition Control Module (ICM).

Electronic Pressure Control (EPC):Controls line pressure in the transmission.

Electric Secondary Air Injection (EAIR):A pump-driven system for providing secondary air using an electric air pump.

Engine:A machine designed to convert thermal energy into mechanical energy to produce force or motion.

Engine Coolant Temperature (ECT):The temperature of the engine coolant.

Engine Fuel Temperature (EFT):Temperature of the fuel in the fuel rail.

Engine RPM (RPM):Indicates engine rpm.

EPC:Electronic Pressure Control.

EVAP:Evaporative Emission.

Evaporative Emission (EVAP):A system to prevent fuel vapor from escaping into the atmosphere. Typically includes a charcoal canister to store fuel vapors.

Exhaust Gas Recirculation (EGR):Reducing NOx emissions levels by adding exhaust gas to the incoming air/fuel mixture.

4R44E:4 speed, Rear wheel drive, 440 lb-ft, Electronic transmission.

4R55E:4 speed, Rear wheel drive, 550 lb-ft, Electronic transmission.

4R70W:4 speed, Rear wheel drive, 700 lb-ft, Wide ratio transmission.

4V:Four Valve.

4x4 Low (4x4L):Indicates the 4x4 Low range of the transfer case has been selected.

4x4L:4x4 Low.

F4E:F Level (119 lb-ft) 4 speed Electronic transmission.

Failure Mode Effects Management (FMEM):An alternative vehicle operation strategy that protects vehicle function from the adverse effect of an EEC system failure.

Fan:A device designed to supply a current of air. A fan may also have a frame, motor, wiring harness and the like.

Fan Control (FC):Controlling the engine cooling fan.

FC:Fan Control.

FF:Flexible fuel.

Flexible Fuel (FF):A system capable of using a variety of fuels for vehicle operation.

FMEM:Failure Mode Effects Management.

Four Valve (4V):Four valves, two intake and two exhaust, per cylinder.

FP:Fuel Pump.

FPDM:Fuel Pump Driver Module.

FPM:Fuel Pump Monitor.

FPRC:Fuel Pressure Regulator Control.

Freeze Frame:A block of memory containing the vehicle operating conditions for a specific time.

FTP:Fuel Tank Pressure.

Fuel:Any combustible substance burned to provide heat or power. Typical fuels include gasoline and diesel fuel. Other types of fuel include ethanol, methanol, natural gas, propane or in combination.

Fuel Pressure Regulator Control (FPRC):Controls the fuel pressure regulator. Used primarily to provide extra fuel during cold starts.

Fuel Pump (FP):A pump used to deliver fuel to the engine.

Fuel Pump Driver Module (FPDM):A module that controls an electric fuel pump.

Fuel Pump Monitor (FPM):Monitors operation of the fuel pump.

Fuel Rich/Lean:A qualitative evaluation of air/fuel ratio based on an A/F ratio known as stoichiometry or 14.7:1. In the EEC system, rich/lean is determined by a voltage signal from the HO2S. An excess of oxygen (lean) is indicated by an HO2S voltage of less than .4 volts; a rich condition is indicated by an HO2S voltage of greater than .6 volts.

Fuel Tank Pressure (FTP):Internal pressure of the fuel tank and the EVAP system.

FWD:Front Wheel Drive.

GEN:Generator.

Generator (GEN):A rotating machine designed to convert mechanical energy into electrical energy.

GND:Ground.

Goose:A brief opening and closing of the throttle (Dynamic Response test).

Ground (GND):An electrical conductor used as a common return for an electric circuit(s) and with a relative zero potential.

GVW:Gross Vehicle Weight.

Hall Effect:A process where current is passed through a small slice of semi-conductor material at the same time as a magnetic field to produce a small voltage in the semi-conductor.

Hard Fault:A fault currently present in the system.

Hardware Limited Operating Strategy (HLOS):A mode of operation where the PCM replaces output commands with fixed values in response to certain PCM malfunctions.

HC:Hydrocarbon.

HDL:Headlamp.

Headlamp (HDL):Input that indicates status of the headlamps.

Heated Oxygen Sensor (HO2S):An Oxygen Sensor (O2S) that is electrically heated.

HFC:High Fan Control.

HFP:High Fuel Pump.

High Fan Control (HFC):Controlling the high speed cooling fan.

High Fuel Pump (HFP):Controls the high speed fuel pump.

High Swirl Combustion (HSC):A cylinder and piston configuration that causes swirling of the air/fuel mixture in the cylinder.

HLOS:Hardware Limited Operating Strategy.

HO:High Output.

HO2S:Heated Oxygen Sensor.

HSC:High Swirl Combustion.

IAC:Idle Air Control.

IAT:Intake Air Temperature.

ICM:Ignition Control Module.

Idle Air Control (IAC):Electrical control of throttle bypass air.

IDM:Ignition Diagnostic Monitor.

IFS:Inertia Fuel Shutoff.

IGN GND:Ignition Ground.

Ignition:System used to provide high voltage spark for internal combustion engines.

Ignition Control Module (ICM):The module that controls the ignition system.

Ignition Diagnostic Monitor (IDM):Monitors operation of the ignition system.

IMRC:Intake Manifold Runner Control.

IMT:Intake Manifold Tuning.

Inertia Fuel Shutoff (IFS):An inertia system that shuts off the fuel delivery system when activated by predetermined force limits.

Injection Pressure (IP):Pressure in the fuel rail.

Injector:A device for delivering metered pressurized fuel to the intake system or the cylinders.

Intake Air:Air drawn through a cleaner and distributed to each cylinder for use in combustion.

Intake Air Temperature (IAT):The temperature of the intake air.

Intake Manifold Runner Control (IMRC):Controls airflow through runners in the intake manifold.

Intake Manifold Tuning (IMT):Control of airflow through runners in a split intake manifold.

Integrated Electronic Ignition (EI):An Electronic Ignition system that has the Ignition Control Module (ICM) integrated into the PCM.

Intermittent:A fault that may not be present or identifiable at the present time.

IP:Injection Pressure.

KAM:Keep Alive Memory.

KAPWR:Keep Alive Power.

Keep Alive Memory (KAM):A portion of the memory within the PCM that must maintain power even when the vehicle is not operating.

Keep Alive Power (KAPWR):Dedicated, unswitched power circuit that maintains KAM.

Key On Engine Off Self-Test:A test of the EEC system conducted by the PCM with power applied and the engine at rest.

Key On Engine Running Self-Test:A test of the EEC system conducted by the PCM with the engine running and the vehicle at rest.

Knock:The sharp metallic sound produced when two pressure fronts collide in the combustion chamber of an engine.

Knock Sensor (KS):Detects engine knock.

KOEO:Key On Engine Off.

KOER:Key On Engine Running.

KS:Knock Sensor.

L:Liters.

LFC:Low Fan Control.

LFP:Low Fuel Pump.

Low Fan Control (LFC):Controlling the low speed cooling fan.

Low Fuel Pump (LFP):Controls the low speed fuel pump.

M/T:Manual Transmission/Transaxle.

MAF:Mass Air Flow.

MAF RTN:Mass Air Flow Return.

Malfunction Indicator Lamp (MIL):A required on-board indicator to alert the driver of an emission related malfunction. May read either "CHECK ENGINE" or "SERVICE ENGINE SOON."

Manifold:A device designed to collect or distribute fluid, air or the like.

Manifold Absolute Pressure (MAP):The absolute pressure of the intake manifold air.

MAP:Manifold Absolute Pressure.

Mass Air Flow (MAF):A system which provides information on the mass flow rate of the intake air to the engine.

Mass Air Flow Return (MAF RTN):A return circuit for the MAF sensor.

MD:Misfire Detection.

Mechanical Secondary Air Injection:A pump driven system for providing secondary air using a belt driven pump.

MFI:Multiport Fuel Injection.

MIL:Malfunction Indicator Lamp.

Misfire:Any event in the cylinder that causes a sudden change in acceleration of the crankshaft.

Misfire Detection (MD):Circuitry designed to detect a misfire by monitoring changes in acceleration of a wheel mounted on the crankshaft.

Module:A self-contained group of electrical/electronic components, which is designed as a single replaceable unit.

Monitor Box:An optional EEC system test device which connects in series with the PCM and its harness and permits measurements of PCM inputs and outputs.

Multiport Fuel Injection (MFI):A fuel-delivery system in which each cylinder is individually fueled.

NAAO:North American Automotive Operations.

Natural Gas (NG):A system capable of using natural gas for vehicle operation.

NC:Normally Closed.

NG:Natural Gas.

NO:Normally Open.

NOx:Oxides of Nitrogen.

O2S:Oxygen Sensor.

OASIS:On-line Automotive Service Information System.

OBD:On Board Diagnostic.

OC:Oxidation Catalytic Convertor.

OCT ADJ:Octane Adjust.

Octane Adjust (OCT ADJ):Can alter engine strategy to compensate for changes in fuel octane.

OHC:Overhead Cam.

On Board Diagnostic (OBD):A system that monitors some or all computer input and control signals. Signal(s) outside of the predetermined limits imply a fault in the system or in a related system.

Open Circuit:A circuit which does not provide a complete path for flow of current.

OSS:Output Shaft Speed.

Output Shaft Speed (OSS):Indicates rotational speed of the transmission output shaft.

Overhead Cam (OHC):An engine configuration that uses a single camshaft positioned above the valves.

Overlay Card:A plastic card used with the monitor box to identify EEC signals for each engine. The card also programs the monitor box for auto mode measurements.

Oxidation Catalytic Convertor (OC):A catalytic convertor system that reduces levels of HC and CO.

Oxygen Sensor (O2S):A sensor which detects oxygen (O2) content in the exhaust gases.

Parameter Identification (PID):Identifies an address in memory which contains vehicle operating information.

Park/Neutral Position (PNP):Indicates the selected non-drive modes of the transmission.

PCM:Powertrain Control Module.

PCV:Positive Crankcase Ventilation.

PF:Purge Flow.

PID:Parameter Identification.

PIP:Profile Ignition Pickup.

PNP:Park/Neutral Position.

Positive Crankcase Ventilation (PCV):Positive ventilation of crankcase emissions.

Power Ground (PWR GND):The main ground circuit in the EEC system.

Power Steering:A system which provides additional force to the steering mechanism, reducing the driver's steering effort.

Power Steering Pressure (PSP):Indicates the pressure in the power steering system.

Power Take Off (PTO):An EEC input signal used to disable On Board Diagnostic Monitors.

Powertrain:The elements of a vehicle by which motive power is generated and transmitted to the driven axles.

Powertrain Control Module (PCM):The module that controls the EEC system.

Pressure Feedback EGR:An EGR system that monitors EGR pressure across a remote orifice to control EGR flow.

Profile Ignition Pickup (PIP):Provides crankshaft or camshaft position information for ignition synchronization.

Programmable Speedometer/Odometer Module (PSOM):A module that processes vehicle speed information for use in various electronic systems. The PSOM can be programmed to accommodate various tire and axle combinations.

PSOM:Programmable Speedometer/Odometer Module.

PSP:Power Steering Pressure.

PTO:Power Take Off.

Pump:A device used to raise, transfer, or compress fluids by suction, pressure or both.

Purge Flow (PF):Amount of fuel vapor burned in the engine.

PWR GND:Power Ground.

Quick Test:A functional diagnostic test of the EEC system consisting of vehicle preparation and hookup, KOEO, KOER and Continuous Memory Self-Tests.

RABS:Rear Antilock Brake System.

REDOX:Reduction Oxidation Catalytic Convertor.

Reduction Oxidation Catalytic Convertor (REDOX):A catalytic convertor system that is designed to operate at high temperatures. At low temperatures, it reduces levels of HC and CO. At high temperatures, it reduces levels of HC, CO, and NOx.

Reference Voltage (VREF):A dedicated circuit that provides a 5.0 volt signal used as a reference by certain sensors.

Relay:A generally electromechanical device in which connections in one circuit are opened or closed by changes in another circuit.

Relay Module (RM):A module containing two or more relays.

Return (RTN):A dedicated sensor ground circuit.

RM:Relay Module.

RPM:Engine RPM.

RTN:Return.

RWD:Rear Wheel Drive.

SC:Supercharged.

Scan Tool (ST):A device that interfaces with and communicates information on a data link.

Secondary Air:Air provided to the exhaust system.

Secondary Air Injection (AIR):A pump driven system for providing secondary air.

Secondary Air Injection Bypass (AIRB):Vents secondary air to atmosphere.

Secondary Air Injection Diverter (AIRD):Diverts secondary air to either the catalyst or the exhaust manifold.

Self-Test:One of three subsets of the EEC system Quick Test: Key On Engine Off, Key On Engine Running, and Continuous Memory.

Sensor:The generic name for a device that senses either the absolute value or a change in a physical quantity such as temperature, pressure or flow rate, and converts that change into an electrical quantity signal.

Sequential Multiport Fuel Injection (SFI):A multiport fuel delivery system in which each injector is individually energized and timed relative to its cylinder intake event. Normally fuel is delivered to each cylinder once per two crankshaft revolutions in four cycle engines and once per crankshaft revolution in two cycle engines.

SFI:Sequential Multiport Fuel Injection.

Shift Indicator Lamp (SIL):A lamp that indicates the preferred shift points for manual transmission/transaxle vehicles.

Shift Solenoid (SS):A device that controls shifting in an automatic transmission.

SHO:Super High Output.

Short Circuit:An undesirable connection between a circuit and any other point.

Signal:A fluctuating electric quantity, such as voltage or current, whose variations represent information.

SIG RTN:Signal Return.

Signal Return (SIG RTN):A dedicated sensor ground circuit that is common to two or more sensors.

SIL:Shift Indicator Lamp.

Solenoid:A device consisting of an electrical coil which, when energized, produces a magnetic field in a plunger which is pulled to a central position. A solenoid may be used as an actuator in a valve or switch.

Spark Output (SPOUT):Desired spark timing information sent from the PCM to the ICM.

Speed:The magnitude of velocity (regardless of direction).

SPOUT:Spark Output.

SS:Shift Solenoid.

ST:Scan Tool.

Switch:A device for making, breaking, or changing the connections in an electrical circuit.

System:A group of interacting mechanical or electrical components serving a common purpose.

3-2 Timing Solenoid (3-2TS):A device that controls the timing valve.

3-2TS:3-2 Timing Solenoid.

2V:Two Valve.

TACH:Tachometer.

Tachometer (TACH):A circuit that provides input for an electronic tachometer display.

TB:Throttle Body.

TC:Traction Control.

TCC:Torque Convertor Clutch.

TCIL:Transmission Control Indicator Lamp.

TCS:Transmission Control Switch.

Test:A procedure whereby the performance of a product is measured under various conditions.

Three Way + Oxidation Catalytic Convertor (TWC+OC):A catalytic convertor system that has both Three Way Catalyst (TWC) and Oxidation Catalyst (OC). Usually secondary air is introduced between the two catalysts.

Three Way Catalytic Convertor (TWC):A catalytic convertor system that reduces levels of HC, CO, and NOx.

Throttle:A valve for regulating the supply of a fluid, usually air or an air/fuel mix, to an engine.

Throttle Body (TB):The device containing the throttle.

Throttle Position (TP):Indicates the position of the throttle plate.

Timing:Relationship between spark plug firing and piston position usually expressed in crankshaft degrees before (BTDC) or after (ATDC) top dead center of the compression stroke.

Torque Convertor:A device which by its design multiplies the torque in a fluid coupling between an engine and transmission/transaxle.

Torque Convertor Clutch (TCC):Controls the application and release of the torque convertor clutch.

TFT:Transmission Fluid Temperature.

TP:Throttle Position.

TR:Transmission Range.

Traction Control (TC):Combines anti-lock braking and axle torque reduction to control wheel slippage.

Transaxle:A device consisting of a transmission and axle drive gears assembled in the same case. Compare "Transmission."

Transmission:A device which selectively increases or decreases the ratio of relative rotation between its input and output shafts. Compare "Transaxle."

Transmission Control Indicator Lamp (TCIL):Indicates that the TCS has been activated.

Transmission Control Switch (TCS):Modifies the operation of electronically controlled transmissions.

Transmission Fluid Temperature (TFT):Indicates temperature of transmission fluid.

Transmission Range (TR):The range in which the transmission is operating.

Turbine Shaft Speed (TSS):Indicates rotational speed of the transmission turbine shaft.

TSB:Technical Service Bulletin.

TSS:Turbine Shaft Speed.

TWC:Three Way Catalytic Convertor.

TWC+OC:Three Way + Oxidation Catalytic Convertor.

Two Valve (2V):Two valves, one intake and one exhaust, per cylinder.

Valve:A device by which the flow of liquid, gas, vacuum, or loose material in bulk may be started, stopped or regulated by a movable part that opens, shuts or partially obstructs one or more ports or passageways. A "Valve" is also the moveable part of such a device.

Vapor Management Valve (VMV):A valve that controls the amount of fuel vapor burned in the engine.

Variable Load Control Module (VLCM):A module that provides variable control of various EEC components.

Variable Reluctance:A process of passing a varying magnetic field through wire windings and inducing a voltage.

VECI Label:Vehicle Emission Control Information Label.

Vehicle Power (VPWR):A switched circuit that provides power to the EEC system. Compare "Battery Positive Voltage (B+)."

Vehicle Speed Sensor (VSS):A sensor which provides vehicle speed information.

VLCM:Variable Load Control Module.

VMV:Vapor Management Valve.

VOM:Volt-Ohm Meter.

VPWR:Vehicle Power.

VREF:Reference Voltage.

VSS:Vehicle Speed Sensor.

WAC:Wide Open Throttle A/C Cut-off.

Warm Up Oxidation Catalytic Convertor (WU-OC):A catalytic convertor system designed to lower HC and CO emissions during engine warm up. Usually located in or near the exhaust manifold.

Warm Up Three-Way Catalytic Convertor (WU-TWC):A catalytic convertor system designed to lower HC, CO, and NOx emissions during engine warm up. Usually located in or near the exhaust manifold.

Wide Open Throttle (WOT):A condition of maximum airflow through the throttle body.

Wide Open Throttle A/C Cut-off (WAC):Turns A/C system off during wide open throttle or certain other operating conditions.

WOT:Wide Open Throttle.

WU-OC:Warm Up Oxidation Catalytic Convertor.

WU-TWC:Warm Up Three-Way Catalytic Convertor.