Part 1 of 2
ACRONYMS AND DEFINITIONSNOTE: This Acronyms and Definitions listing contains technical terms applicable to Ford Motor Company products. It is not intended to be an all-inclusive dictionary of components and their functions. If a detailed description of a particular system or component is desired, refer to the applicable Vehicle System for the specific vehicle being repaired.
2V: Two Valves per engine cylinder.
3V: Three Valves per engine cylinder.
4V: Four Valves per engine cylinder.
4WDIWE: 4-Wheel Drive Integrated Wheel Ends.
4WDL_IL: 4-Wheel Drive Low Indicator Lamp.
4WDMCS: 4-Wheel Drive Mode Command Switch.
4WD_POS1/2/3/4: 4-Wheel Drive Motor Position (1-4).
4WDBWRTN: 4-Wheel Drive Mode Command Switch Return.
4WDT_IL: 4-Wheel Drive Tow Indicator Lamp.
4WDL: 4-Wheel Drive Low Switch.
ABS: Anti-lock Brake System.
A/C: Air Conditioning.
A/CC: Air Conditioning Clutch.
A/CCR: A/C Clutch Control Relay.
ACCS: Air Conditioning Cycling Switch.
ACD: Air Conditioning Demand. A signal input to the PCM from the Air Conditioning control panel.
ACDS: Air Conditioning Diagnostic Switch (Refrigerant Containment Switch).
ACET: Air Conditioning Evaporator Temperature (may also be referred to as Evaporator Air Discharge Temperature).
ACP: Air Conditioning Head Pressure or A/C cycling switch input state.
ACPSW: Air Conditioning Pressure Switch.
ACPT: Air Conditioning Head Pressure Transducer (Switch).
ACP V: Air Conditioning Head Pressure Volts. A voltage input to the PCM from the ACP switch or sensor.
A/D: Analog-to-Digital. Analog-to-Digital signal conversion.
ADC: See ATDC.
AFCM: Alternative Fuel Control Module.
AIR: Secondary Air Injection.
AIRB: Secondary Air Injection Bypass.
Air Diverter: Air Diverter Valve. Part of the EAIR system. Diverts fresh air to the exhaust system when the electric air pump is commanded on.
AIR EVAL: Air System Evaluated. Displays a YES or NO status indicating whether the Air System has been evaluated for OBD (On-Board Diagnostic) purposes.
Air/Fuel Ratio: Air-to-fuel mixture ratio. An air-to-fuel mixture that is 14.7:1 is also called stoichiometry.
AIRM: Secondary AIR pump monitor.
ALTCOM: Alternator Command.
ALTMON: Alternator Monitor.
Ambient Air Temperature: Temperature of the air surrounding an object.
Analog (Electrical/Electronic): An electrical signal that may obtain any value within the voltage limits of the signal.
APP: Accelerator Pedal Position
ARB: Air Resource Board.
ARPMIDES: Ancillary RPM Desired. RPM required to maintain the vehicle speed commanded by Speed Control Command Switch (SCCS) inputs.
ASCII: American Standard Code for Information Interchange.
ATDC: After Top Dead Center. The location of the piston after it has reached the top of its stroke. Measured in degrees of crankshaft rotation.
AWD: All-Wheel Drive.
BARO: Barometric Pressure.
Base Idle: Idle RPM determined by the throttle lever hardset on the throttle body.
Base Timing: Spark advance in degrees before top dead center of the base engine without any control from the PCM.
Battery Positive Voltage (B+): The positive (+) voltage from the battery or any circuit connected directly to the battery.
BATTEMP: Battery Temperature.
BJB: Battery Junction Box.
BOB: Breakout Box. A test device which connects in series to the PCM and PCM harness.
BPA: Brake Pedal Applied. Typically located on the braking system master cylinder. Can be hydraulic or electric.
BPP: Brake Pedal Position.
BPS: Brake Pedal Switch\Speed Control Deactivation.
BTDC: Before Top Dead Center. The location of the piston before it has reached the top of its stroke. Measured in degrees of crankshaft rotation.
Bus + or Bus - : Multiplex circuits that carry standard corporate protocol (SCP) or controller area network (CAN) data from module to module and to the data link connector (DLC).
BVREF: Buffer Voltage Reference. A dedicated circuit that provides approximately a 5.0 volt signal used as a reference by certain sensors.
CAC: Charge Air Cooler. Formerly known as Intercooler. A device which lowers the temperature of pressurized intake air.
CAFE: Corporate Average Fuel Economy. A set of federal requirements and regulations which govern fuel economy standards.
CAN: Controller Area Network.
CANP: Canister Purge Solenoid.
CANVNT: Canister Vent.
Catalyst: Catalytic converter. An in-line exhaust system device used to reduce the level of engine exhaust emissions.
CAT EVAL: Catalyst System Evaluated. This item indicates YES when the Catalyst Efficiency Monitor has successfully completed.
CCM: Comprehensive Component Monitor.
CD A through J: Coil Driver 1 through 10.
Centralized Testing Facility: State government operation. Provides inspection/maintenance (IM) and safety inspections.
CGND: Case Ground. Provides a ground source for the PCM case.
CHT: Cylinder Head Temperature. Units are displayed in either degrees Celsius or Fahrenheit.
CHTIL: Cylinder Head Temperature Indicator Lamp.
CHTV: Cylinder Head Temperature Voltage.
CKP: Crankshaft Position.
CKP+, CKP-: CKP+ is the CKP sensor signal circuit. CKP- is the signal return circuit.
CL: Closed Loop. An operating condition or mode which enables operation based on sensor feedback.
CMCV: Charge Motion Control Valve.
CMCVM: Charge Motion Control Valve Monitor.
CMP, CMP1, CMP2: Camshaft Position.
CMPFM: Camshaft Position Failure Mode. Indicates when the PCM identifies a CMP fault.
CMS: Catalyst Monitor Sensor. Downstream HO2S.
CMVSS: Canadian Motor Vehicle Safety Standards.
CO: Carbon Monoxide. A colorless, odorless and toxic gas that is a component of auto exhaust emissions.
CO2: Carbon Dioxide. A colorless, odorless gas that is a normal by-product of the combustion of fuel.
Coil: A device consisting of windings around an iron core. In a spark ignition system, designed to increase voltage.
Cold Soak: Time given to a vehicle to sit at a low temperature, typically below 20°C (68°F), until the temperature of external and internal components stabilize.
CONT: Continuous Memory. The portion of keep alive memory (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.
COP: Coil On Plug. Ignition coil on plug assembly.
CPP: Clutch Pedal Position.
CPP Switch: Clutch Pedal Position Switch. Located on the clutch pedal and detects when the clutch pedal is pressed.
CQIS: Common Quality Indicator System.
CSE GND: Case Ground.
CT: Closed Throttle Mode. A mode when the PCM varies the pulse width of the fuel injectors to obtain the air/fuel mixture appropriate for closed throttle operation.
CTO: Clean Tach Output. Signal used to drive the instrument panel tachometer.
DC: 1. Direct Current. Electric current flowing in one direction. 2. Duty Cycle. The voltage measurement of ON time versus the full cycle period, expressed in percent.
DCL: Data Communication Link. A communication path between various in-vehicle electronic modules.
DI: Distributor Ignition. A system in which the ignition coil secondary circuit is sequenced by a distributor.
Digital: Controls process information by switching the current or voltage ON and OFF.
DIS: Distributorless Ignition System. A system in which the ignition coil secondary circuit is sequenced without a distributor.
DLC: Data Link Connector. J1962 connector providing access to vehicle diagnostic information.
DMM: Digital Multimeter.
DOHC: Dual Overhead Cam. An engine configuration that uses 2 camshafts positioned above the valves.
DOL: Data Output Line. A circuit that sends certain information from the PCM to the instrument cluster.
DPFEGR: Differential Pressure Feedback Exhaust Gas Recirculation. System that uses a pressure transducer to control the operation of the EGR Vacuum Regulator Valve.
DRI: Deposit Resistant Injector. A fuel injector designed to prevent build-up of carbon and other unwanted deposits.
DTM: Diagnostic Test Mode. A level of capability in an OBD system.
DTC: Diagnostic Trouble Code. An alpha/numeric identifier for a fault condition identified by the OBD System.
E-85: Fuel containing 85% ethanol alcohol.
EAIR: Electric Secondary Air Injection. A pump-driven system for providing secondary air using an electric air pump.
EAIRM: Electric Air Pump Monitor.
ECT: Engine Coolant Temperature. Displayed in either Celsius or Fahrenheit.
ECTV: Engine Coolant Temperature Voltage.
ECU: Electronic Control Unit. A module that handles the control strategy and monitors system inputs or outputs.
EEC: Electronic Engine Control.
EEC-V: Fifth generation EEC system.
EFTA: Engine Fuel Temperature A (bank 1).
EFTAV: Engine Fuel Temperature A Voltage.
EFTB: Engine Fuel Temperature B (bank 2).
EFTBV: Engine Fuel Temperature B Voltage.
EGR: Exhaust Gas Recirculation. A process in which a small amount of exhaust gas is routed into the combustion chamber.
EGR EVAL: Exhaust Gas Recirculation System Evaluated. EGR EVAL will display YES when the monitor is complete.
EGRMC (1-4): Electric Exhaust Gas Recirculation Motor Control Valve.
EGRMDSD: Electric Exhaust Gas Recirculation Motor Desired position. The PID name used to operate the EEGR valve.
EGRT: Exhaust Gas Recirculation Valve Temperature. A temperature sensor that is threaded into the bottom of the intake plenum.
EGRVR: Exhaust Gas Recirculation Vacuum Regulator. A solenoid which controls vacuum to the EGR valve by varying the duty cycle signal from the PCM.
EGRVRA: Exhaust Gas Recirculation Vacuum Regulator Actual (volt). The actual state of the commanded output.
EGRVRF: Exhaust Gas Recirculation Vacuum Regulator Fault. Represents whether a fault exists in the EGRV circuit.
EI: Integrated Electronic Ignition. An Electronic Ignition system that has the Ignition Control Module (ICM) integrated into the PCM.
EI-HDR: Electronic Ignition-High Data Rate. Formerly known as Electronic Distributorless Ignition System.
EI-LDR: Electronic Ignition-Low Data Rate. Formerly known as Distributorless Ignition System.
EMI: Electromagnetic Interference. Usually caused by ignition voltage spikes, solenoids, relay operation or noisy generator contacts.
EOL: End Of Line. A system designed specifically for use at assembly plants to make sure all new vehicles perform to design specifications.
EOT: Engine Oil Temperature.
EPA: Environmental Protection Agency (United States Government).
EPROM: Erasable Programmable Read-Only Memory. An electronic component in the PCM that allows the electronic storage of information.
ESM: EGR System Module.
ESOF: Electronic Shift-on-the-Fly.
ETB: Electronic Throttle Body
ETC: Electronic Throttle Control
ETCIL: Electronic Throttle Control Indicator Lamp
ETCVREF: Voltage Reference (5V) for ETC (APP VREF, TP VREF).
EVAP: Evaporative Emissions. A system to prevent fuel vapor from escaping into the atmosphere.
EVAPCP: Evaporative Canister Purge Solenoid. A solenoid which controls the venting of fuel vapor from the evaporative emissions canister into the intake manifold for combustion.
EVAPCPF: Evaporative Canister Purge Solenoid Fault. Identifies whether an electrical fault exists for the current commanded state.
EVAPCV: Evaporative Canister Vent Solenoid. A solenoid which seals the EVAP system from the atmosphere during the EVAP monitor test.
Evaporative Emissions Canister: An evaporative emission canister, containing activated charcoal which absorbs and holds fuel vapors.
EVAPPDC: Evaporative Canister Purge Duty Cycle. The duty cycle commanded to the EVAP Canister Purge Solenoid by the PCM.
EVO: Electronic Variable Orifice.
Electric VMV: Electric Vapor Management Valve also known as the EVAP Canister Purge Valve.
EWP: Electric Water Pump.
Exciter Ring: A toothed or notched iron or steel disk.
FAN: Fan Speed.
FANSS: Fan Speed Sensor.
FC, FC1, FC2, FC3: Fan Control.
FCS: Fuel Control Solenoid.
FCIL: Fuel Cap Off Indicator Lamp. Indicates that the fuel filler cap is not properly installed.
FCV: Fan Control - Variable.
FEAD: Front End Accessory Drive.
FEPS: Flash EEPROM Programming Signal. An 18-volt DC signal input from the diagnostic tool used by the PCM to initiate programming.
FFV: Flexible Fuel Vehicle.
FICM: Fuel Injector Control Module.
FIM: Fuel Indicator Module.
FLI: Fuel Level Input. Provides information on the amount of liquid fuel in the fuel tank. Used by the EVAP monitor to calculate the fuel tank vapor volume. Displayed as a percentage.
FLI V: Fuel Level Input Voltage.
FMEM: Failure Mode Effects Management. Operating strategy that maintains limited vehicle function in the event of a PCM or EEC component failure.
FP: 1. Fuel Pump. Indicates whether the pump has been commanded ON or OFF by the PCM. 2. Fuel Pump (Modulated). Fuel pump duty cycle percentage.
FPC: Fuel Pump Control.
FPDM: Fuel Pump Driver Module. A module that controls the electric fuel pump.
FPF: Fuel Pump Fault. Identifies whether a fault exists in the FP circuit.
FPM: Fuel Pump Monitor. Monitors the Fuel Pump / circuits for faults.
Freeze Frame: A block of memory containing the vehicle operating conditions at a specific time.
FRP: Fuel Rail Pressure.
FRP V: Fuel Rail Pressure Voltage. A voltage input to the PCM from the Fuel Rail Pressure Sensor.
FRT: Fuel Rail Temperature.
FSC: Fail-Safe Cooling.
FSSW: Fuel Select Switch. An output signal between the PCM and FICM which determines the fuel delivery mode.
FTP: Fuel Tank Pressure.
FTP V: Fuel Tank Pressure Voltage. From the FTP transducer.
FUEL PR: Fuel Pressure. Measurement of the force of the fuel delivered by the fuel pump.
FUELPW: Fuel Pulse Width. Displays the commanded pulse width at time of last data update.
FUELPW1: Fuel Injector Pulse Width #1. Corresponds to injectors normally affected by HO2S1.
FUELPW2: Fuel Injector Pulse Width #2. Corresponds to injectors normally affected by HO2S2.
FUELSYS: Fuel System Status (OPEN/CLOSED Loop). Formerly known as LOOP.
Fuel Tank Vapor Valve: A valve mounted in the top of the fuel tank that vents excess vapor and pressure from the fuel tank into the Evaporative Emission Control System.
FWD: Front Wheel Drive.
GEM: Generic Electronic Module.
GEN: Generator.
GENIL: Generator Indicator Lamp. A PCM output signal used to control the charging system indicator.
GENLI: Generator Load Input. An input signal utilized by the PCM to monitor charging system operation and determine the system voltage.
GENRC: Generator Regulator Control. A PCM output signal used to control the voltage regulator.
GENF: Generator Output Fault
GENFDC: Generator Field Control Output
GFS: Generator Field Signal
GND: Ground
GPM: Grams per Mile. Also known as Gallons per Minute.
Green State Vehicle: Formally known as California Emissions. A vehicle that is equipped with California on-board diagnostics.
GSS: Gear Select Solenoid
GVW: Gross Vehicle Weight
Hall effect: A process where current is passed through a small portion of semiconductor material and a magnetic field to produce a small voltage in the semiconductor.
Hard Fault: A fault currently present in the system.
HC: 1. Hydrocarbon. A by-product of combustion and a component of auto exhaust emissions. 2. High Compression.
HFC: High Fan Control
HFCF: High Fan Control Fault. Identifies if there is a fault in the HFC circuit.
HFP: High Fuel Pump
HLOS: Hardware Limited Operating Strategy. A mode of operation where the POM replaces output commands with fixed values in response to internal PCM malfunctions.
HO: High Output
HO2S: Heated Oxygen Sensor. Provides information on rich or lean exhaust conditions to the PCM.
Hot Soak: Period of time after an engine operates where localized combustion heat dissipates throughout the engine.
HTR11, HTR12, HTR13, HTR21, HTR22: HO2S Heater. Heater element for the HO2S sensor.
Hydrogen: Chemical symbol H. Highly flammable gas.
Hz: Hertz. Cycles per second.
EAC: Idle Air Control. Electrical control of throttle bypass air.
EAT: Intake Air Temperature
IATV: Intake Air Temperature Voltage. Actual voltage drop across the IAT sensor.
IAT2: Intake Air Temperature 2. Used on supercharged vehicles.
IAT2V: Intake Air Temperature 2 Voltage. Actual voltage drop across the IAT2 sensor.
IC: Integrated Circuit. A small semi-conductor device capable of many separate circuit functions.
ICM: Ignition Control Module. The module that controls the ignition system.
IFDM: Integrated Fuel Delivery Module
IFS: Inertia Fuel Shut Off
IGN GND: Ignition Ground
Ignition: System used to provide high voltage spark for internal combustion engines.
IGN_KEY (IGKY): Ignition Key
IGN_SW (IGSW): Ignition Switch Position
ILC: Generator I-Line Control. A generator feedback signal provided to the PCM.
IMRC: Intake Manifold Runner Control. Controls or modifies airflow in the intake air system.
IMRCM: Intake Manifold Runner Control Monitor. Monitors the IMRC circuits for faults.
IMTV, IMTV1, IMTV2: Intake Manifold Tuning Valve. Controls airflow through runners in a split intake manifold.
INJ1, INJ2, INJ3, INJ4, INJ5, INJ6, INJ7, INJ8, INJ9, INJ10: Injector number or its signal output from the PCM.
Injector: A device for delivering metered pressurized fuel to the intake system or the cylinders.
Intake Air: Air drawn through a filter and distributed to each cylinder for use in combustion.
Intercooler: See CAC.
IPATS: Integrated Passive Anti-Theft System.
ISO: International Standards Organization.
KAM: keep Alive Memory. A portion of the memory within the PCM that must have power even when the vehicle is not operating.
KAPWR: Keep Alive Power. Dedicated, unswitched power circuit that maintains KAM.
KEYPWR: Key Power. Battery voltage supplied when the ignition key is in the ON position.
Knock: The sharp metallic sound produced when 2 combustion pressure fronts collide in the combustion chamber of an engine.
KOEO Self-Test: Key On Engine Off self-test. A test of the EEC system conducted by the PCM with power applied and the engine at rest.
KOER Self-Test: Key On Engine Running sell-test. A test of the EEC system conducted by the PCM with the engine running and the vehicle at rest.
Km/h: Kilometers Per Hour
KPA: Kilopascal. Unit of pressure. 3.386 kPa = 1 inch of mercury (Hg.).
KS: Knock Sensor. Detects engine knock.
L: Liters. The unit of volume in the metric measuring system. One liter equals 1.06 quarts .
LEV: Low Emissions Vehicle.
LFC: Low Fan Control.
LONGFT1, LONGFT2: Long-Term Fuel Trim. Fuel flow adjustment determined by the PCM.
LOOP: Indicates OPEN or CLOSED loop status.
LPG: Liquefied Petroleum Gas.
LPLR: Low Pressure Low Resistance fuel injector.
M-85: Fuel containing 85% methanol alcohol.
MAF: Mass Air Flow.
MAF RTN: Mass Air Flow Return. A return circuit for the MAF sensor.
MAP: Manifold Absolute Pressure. The internal pressure of the intake manifold.
MFC: Medium Fan Control.
MFI: Multiport Fuel Injection. A fuel-delivery system in which each cylinder is individually fueled.
MFP: Modulated Fuel Pump.
Microprocessor: A device that controls logic and arithmetic functions.
MIL: Malfunction Indicator Lamp. An indicator lamp alerting the driver of an emission related malfunction.
MISF: Misfire. Any event in the cylinder that causes a sudden change in acceleration of the crankshaft.
MON: Motor Octane Number.
MSOF: Manual Shift-on-the-Fly.
MY: Model Year.