Part 2 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.
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. A dedicated and unswitched power circuit that maintains KAM.
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 self-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 equals 1 inch of mercury (Hg).
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
LONGFT: Long-Term Fuel Trim. Fuel flow adjustment determined by the PCM.
LPLR: Low Pressure Low Resistance fuel injector
M-85: Fuel containing 85% methanol alcohol
MAF: Mass Air Flow
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
MIL: Malfunction Indicator Lamp. An indicator lamp alerting the driver of an emission related concern.
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
NA: Naturally Aspirated. An engine that is not supercharged or turbocharged.
NC: Normally Closed
NGS: New Generation Self-Test Automatic Readout (STAR) tester
NO: Normally Open
NOx: Oxides of Nitrogen. Gasses formed at high combustion temperatures.
O2S11, O2S12, O2S13, O2S21, O2S22, O2S23: Oxygen Sensor. Provides information on rich or lean exhaust conditions to the PCM.
OASIS: On-line Automotive Service Information System
OBD, OBD-II: On-Board Diagnostics, On-Board Diagnostics Second Generation. A system that monitors the PCM input and output control signals.
OCT ADJ: Octane Adjust. Compensating strategy that adjusts for changes in fuel octane.
OEM: Original Equipment Manufacturer
OHC: Overhead Cam. An engine configuration that uses a single camshaft positioned above the valves.
OL: Open Loop. An operating condition based on instructions not modified by PCM feedback.
ORVR: On-Board Refueling Vapor Recovery
OSC: Output State Control
OSS: Output Shaft Speed
OTM: Output Test Mode
PATS: Passive Anti-Theft System
PCM: Powertrain Control Module. Formerly known as the electronic engine control (EEC) processor.
PCMRC: Powertrain Control Module Relay Control
PCV: Positive Crankcase Ventilation. A system which allows the controlled flow of crankcase vapors into the combustion chamber.
PID: Parameter Identifier. Identifies an address in the PCM memory which contains operating information.
PIP: Profile Ignition Pickup. Provides crankshaft position information for ignition synchronization.
PPM: Parts per Million. A measure used in emission analysis.
PROM: Programmable Read-Only Memory. Similar to ROM, except without program instructions.
PSP: Power Steering Pressure. Indicates the pressure in the power steering system.
PSPT: Power Steering Pressure Transducer
PTO: Power Take-Off
PW: Pulse Width. The length of time an actuator, such as a fuel injector, remains energized.
PWM: Pulse Width Modulation. Controls the intensity of an output by varying the signal duty cycle.
PWR GND: Power Ground. The main ground circuit in the EEC system.
RABS: Rear Anti-Lock Brake System
RAM: Random Access Memory. Memory into which information can be written as well as read.
REM: Rear Electronic Module
RF: Radio Frequency
RFI: Radio Frequency Interference
RFS: Returnless Fuel System
ROM: Read-Only Memory. Computer memory that can be accessed and used, but not altered.
RPM: Revolutions Per Minute
RTN: Return. A dedicated sensor ground circuit.
RWD: Rear Wheel Drive
SAE: Society of Automotive Engineers
SBS: Supercharger Bypass Solenoid or its signal output from the PCM
SC: Supercharged or Supercharger
SCB: Supercharger Bypass
SCBC: Supercharger Bypass Control. A system that allows manifold vacuum to be bled away from the supercharger wastegate actuator to allow for maximum boost.
SCP: Standard Corporate Protocol
SFI: Sequential Multiport Fuel Injection. A multiport fuel delivery system in which each injector is individually energized and timed relative to its cylinder intake event.
SHRTFT: Short-Term Fuel Trim. Fuel flow adjustment in response to the HO2S sensor(s) input during closed-loop operation.
SIG RTN: Signal Return. A dedicated sensor ground circuit that is common to 2 or more sensors.
SME: Society of Manufacturing Engineers
SOHC: Single Overhead Cam
TA: Traction Assist
TAC: Throttle Actuator Control
TACH: Tachometer
TACM, TACMP, TACMN, TACP (+/-): Throttle Actuator Control Motor ± used in the ETC system.
TB: Throttle Body. A device that controls airflow through the engine via a butterfly valve and has an air bypass channel around the throttle plate.
TC: 1. Traction Control. Combines anti-lock braking and axle torque reduction to control wheel slippage. 2. Turbocharger.
TDC: Top Dead Center
TP: Throttle Position sensor. A potentiometer that provides throttle angle and rate information for the PCM.
TP1: Throttle Position 1
TP2: Throttle Position 2
TSB: Technical Service Bulletin. Notifies technician of any known vehicle concerns, procedures, or general repair information.
VCT, VCT1, VCT2: Variable Camshaft Timing. VCT1 and VCT2 on V engines where applicable.
VECI: Vehicle Emission Control Information
VIN: Vehicle Identification Number. A unique identification number given to every vehicle produced. Includes information about the year, model, engine, and plant origin of the vehicle.
VMV: Vapor Management Valve. Also known as EVAPCP. Refer to EVAPCP.
VBPWR: Vehicle Buffered Power. A PCM-supplied power source that supplies regulated voltage.
VPWR: Vehicle Power. A switched circuit that provides power to the EEC system. Compare to battery voltage (B+).
VREF: Reference Voltage. A dedicated circuit that provides an approximately 5.0 volt signal used as a reference by certain sensors.
WAC: Wide Open Throttle A/C Cut-Off. Turns the A/C system off during wide open throttle or certain other operating conditions.
WOT: Wide Open Throttle. A condition of maximum airflow through the throttle body.
Transmissions:
NOTE: The automatic transmission naming convention is as follows:
- The first character, a number, is the number of forward gears.
- The second character, either the letter F or R, represents front (transaxle) or rear (transmission) wheel drive.
- The next set of characters, a grouping of numbers, represents the design torque capacity of the transmission/transaxle.
- The last character, if used, is one of the following:
- E for electronic shift
- N for non-synchronous shift
- S for synchronous shift
- W for wide ratio
As an example, for the 4F27E transaxle, the number of forward gears is 4, the character F indicates front transaxle, 27 represents 270 ft-lbs of torque capacity and the character E represents an electronic shift.
- A/T: Automatic Transmission
- CCS: Coast Clutch Solenoid
- EPC, EPC1, EPC2: Electronic Pressure Control
- ESS: Electronic Shift Scheduling
- ISS: Intermediate/Input Shaft Speed Sensor
- M/T: Manual Transmission/Transaxle
- OCS: Overdrive Cancel Switch
- OSS: Output Shaft Speed. Indicates the rotational speed of the transmission output shaft.
- PNP: Park/Neutral Position switch.
- REVERSE or REV: Transmission Reverse Switch Input
- SSA/SSB/SSC/SSD/SSE: Shift solenoids. Devices in an automatic transmission that control the shifting by varying fluid flow when commanded by the PCM.
- SS1/SS2/SS3: Shift solenoids. Devices in an automatic transmission that control the shifting by varying fluid flow when commanded by the PCM.
- TCC/TCCH: Torque Converter Clutch. When energized, causes a mechanical engagement and disengagement of the torque converter clutch.
- TCIL: Transmission Control Indicator Lamp. Indicates that the TCS has been activated.
- TCS: Transmission Control Switch. Modifies the operation of electronically controlled transmissions.
- TFT: Transmission Fluid Temperature. Indicates the temperature of transmission fluid
- TR, TR1, TR2, TR3, TR4: Transmission Range. The range in which the transmission is operating.
- TSS: Turbine Shaft Speed. Indicates the rotational speed of the transmission turbine shaft.
- VSS: Vehicle Speed Sensor. A magnetic pickup device that generates an AC signal that is proportional to the vehicle speed.
- VSOUT: Vehicle Speed Output. A pulse width modulated vehicle speed signal.