M - V
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 serviced.
M-85 - Fuel containing 85% methanol alcohol.
MAF - Mass Air Flow. Used to measure the mass (weight) of the air entering the engine.
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 digital processor on a chip which performs arithmetic and control logic.
MIL - Malfunction Indicator Lamp. An indicator lamp alerting the driver of an emission related malfunction. May also read "CHECK ENGINE" or "SERVICE ENGINE SOON."
MISF - Misfire. Any event in the cylinder that causes a sudden change in acceleration of the crankshaft.
MON - Motor Octane Number.
Monolithic Substrate - The ceramic honeycomb structure used in the catalytic converter.
MSOF - Manual Shift-on-the-Fly.
MY - Model Year.
NA - Naturally Aspirated. Engine that is not supercharged or turbocharged.
NAAO - North American Automotive Operations.
NC - Normally Closed.
NG - Natural Gas. A system capable of using natural gas for vehicle operation.
NGS - New Generation STAR (Self-Test Automatic Readout) tester.
NGVM - Natural Gas Vehicle Module.
NO - Normally Open.
NOx - Oxides of Nitrogen. Formed at high combustion temperatures.
NVH - Noise, Vibration, Harshness. A classification of vehicle concerns.
OASIS - On-line Automotive Service Information System.
OBD, OBD-II - On-Board Diagnostics, On-Board Diagnostics Second Generation. A system that monitors PCM input and output control signals.
On-Demand Test - Technician initiated "KOEO" and "KOER" tests performed by the PCM.
OC - Oxidation Catalytic converter. A catalytic converter system that reduces levels of HC and CO.
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.
OWL - Overheat Warning Lamp or its signal output from the PCM. Turns the TEMP warning lamp ON when engine oil temperature exceeds safe limits.
Open Circuit - A circuit which does not provide a complete path for flow of current.
OL - Open Loop. An operating condition based on instructions not modified by PCM feedback.
O2S 11/12/21/22 - Oxygen Sensor and its relative position in the exhaust system. Detects oxygen content in exhaust gasses.
OSC - Output State Control.
OSS - Output Shaft Speed.
Ozone - A blue gaseous form of oxygen (O3) formed naturally by electric discharge or exposure to ultraviolet radiation.
Particulate - Small solid matter found in exhaust gases, especially prevalent in diesel engines.
PATS - Passive Anti-Theft System.
PATSIL - Passive Anti-Theft System Indicator Light.
PATSIN - Passive Anti-Theft System Receive Signal.
PATSOUT - Passive Anti-Theft System Transmit Signal.
PATSTRT - Passive Anti-Theft System Starter Relay Control.
PCM - Powertrain Control Module. Formerly known as the EEC (Electronic Engine Control) Processor.
PCV - Positive Crankcase Ventilation. A system which allows the controlled flow of crankcase vapors into the combustion chamber.
PF - Purge Flow. Amount of fuel vapor burned in the engine.
Photochemical - Term describing the action of light on air pollutants which results in creating smog.
PID - Parameter Identifier. Identifies an address in PCM memory which contains operating information.
Powertrain - Engine and transmission/transaxle components.
Pressure - Absolute - A pressure referenced to a perfect vacuum.
Pressure - Atmospheric - The pressure of the surrounding air at any given temperature and altitude. Sometimes called Barometric Pressure.
Pressure - Barometric - Pertaining to atmospheric pressure or the results obtained by a barometer.
Pressure - Differential - The pressure difference between two regions, such as between the intake manifold and atmospheric pressure.
Pressure - Gage - The amount by which absolute pressure exceeds the ambient atmospheric pressure.
PIP - Profile Ignition Pickup. Provides crankshaft position information for ignition synchronization.
Potentiometer - An adjustable resistance component commonly used as a sensor (Example: TP Sensor).
PPM - Parts Per Million. A measure used in emission analysis.
PROM - Programmable Read-Only Memory. Similar to ROM except without program instructions.
Protocol - A set of rules for the exchange of information on a network.
PSOM - Programmable Speedometer/Odometer Module. A module that processes vehicle speed information.
PSP - Power Steering Pressure. Indicates the pressure in the power steering system.
PSP V - Power Steering Pressure Input Voltage.
PTEC - PowerTrain Electronic Controller.
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.
Quick Test - A series of diagnostic tests of the EEC system consisting of KOEO, KOER and Continuous Memory Self-Tests. Results are displayed as a series of DTCs.
RABS - Rear Antilock Brake System.
RAM - Random Access Memory. Memory into which information can be written as well as read.
REDOX - Reduction Oxidation Catalytic converter. A catalytic converter system designed to operate at high temperatures.
Regulator - Controls the alternator/generator field current to maintain proper battery charge. Contained within the PCM in smart charging applications.
Relay - An electromechanical device in which connections in one circuit are opened or closed by changes in another circuit.
REM - Rear Electronic Module.
Repetitive Spark - Multiple firings of individual spark plugs at engine speeds below 1000 RPM to improve idle quality and improve emissions.
RF - Radio Frequency.
RFI - Radio Frequency Interference.
RFS - Returnless Fuel System.
RM - Relay Module. A module containing two or more relays.
ROM - Read-Only Memory. Computer memory that can be accessed and utilized, but not altered.
RON - Research Octane Number.
Routine - A group of related tasks, such as a series of diagnostic tests.
RPM - Revolutions Per Minute.
RS - Reverse Switch.
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.
SBC - Supercharger Bypass Control. A system that allows manifold vacuum to be bled away from the supercharger wastegate actuator to allow for maximum boost.
SBCF - Supercharger Bypass Control Fault. Identities whether a fault exists in the Supercharger Bypass circuit.
SCICP - Supercharger Intercooler Pump Control.
SCICPF - Supercharger Intercooler Pump Control Fault.
SCIPC - The PID to monitor the operation of the Supercharger and Charge Air Cooler pump.
SCP - Standard Corporate Protocol.
Self-Test - See Quick Test.
Sensor - A device that detects the value or change in a physical quantity, such as temperature, pressure or flow rate, and converts the data into an electrical signal.
SFI - Sequential Multiport Fuel Injection. A multiport fuel delivery system where each injector is individually energized and timed relative to its cylinder intake event.
Shield - A conducting sleeve that surrounds wires to be electronically isolated from electromagnetic interference (EMI).
Short Circuit - An undesirable condition in a circuit where it is terminated at a point other than that intended.
SHRT FT - Short-Term Fuel Trim. Fuel flow adjustment in response to the HO2S sensor(s) input during close-loop operation.
SIG RTN - Signal Return. A dedicated sensor ground circuit that is common to two or more sensors.
SIL - Shift Indicator Lamp.
Smart Driver - A PCM or ECU output driver that can detect faults (open or shorts) on its output circuit.
SME - Society of Manufacturing Engineers.
SOF - Shift-On-the-Fly.
SOHC - Single Overhead Cam.
Solenoid - A device consisting of an electrical coil which produces a magnetic field in a plunger and pulled to a central position.
ST - Scan Tool. A device that interfaces with and communicates information on a data link.
Stoichiometry - An air/fuel mixture that is neither too rich nor too lean. Stoichiometric ratio is 14.7 parts of air for every 1 part of fuel.
Switch - A device for making, breaking, or changing the connections in an electrical circuit.
TA - Traction Assist.
TACH - Tachometer.
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.
Tear Tag - The two-piece adhesive label attached to the PCM to identify its calibration.
Thermistor - A temperature dependent resistor, like that used in CHT and ECT sensors.
Timing - Relationship between spark plug firing and piston position expressed in crankshaft degrees before (BTDC) or after (ATDC) top dead center of the compression stroke.
TMAP - Thermal Manifold Absolute Pressure Sensor. A MAP Sensor that includes a thermistor to measure intake air temperature.
TP - Throttle Position (sensor). A three-wire potentiometer that provides throttle angle and rate information for the PCM.
TP V - Throttle Position Sensor Voltage.
Transducer - A device that receives energy from one medium and transfers it to another. For example, thermal energy is converted to an electrical signal through a temperature probe.
Transmissions/Transaxles:
NOTE: All related items are grouped under the general heading "TRANSMISSIONS" located at the end.
TSB - Technical Service Bulletin. Notifies service personnel of any known vehicle concerns, procedures, or general service information.
Underspeed Mode - A control mode that prevents the engine from stalling in the event it stumbles while running. Also used during engine crank.
Vacuum - Manifold pressure that is reduced below the ambient atmospheric pressure.
Variable Reluctance - A process of passing a varying magnetic field through wire windings and inducing a voltage.
VCT - Variable Camshaft Timing.
VDF - Visctronic Drive Fan.
VECI - Vehicle Emission Control Information label.
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. Controls the flow of fuel vapors out of the carbon canister.
VOM - Volt-Ohm Meter. Readings are indicated by sweep hand on a printed scale rather than a digital (DVOM) display.
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 "Battery Voltage (B+)".
VREF - Reference Voltage. A dedicated circuit that provides approximately a 5.0 volt signal used as a reference by certain sensors.
WAC - Wide Open Throttle A/C Cut-Off. Turns A/C system off during wide open throttle or certain other operating conditions.
Wastegate Control - A device that opens the wastegate in case of overboost from a turbocharger.
WOT - Wide Open Throttle. A condition of maximum airflow through the throttle body.
Zip Tube - Another name for "fresh air duct" or "air inlet duct".
TRANSMISSIONS:
NOTE: The 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 (for example, "27" represents 270 ft/lbs. in the 4F27E 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
^ 4F27E - Also known as the FN Focus automatic transmission.
^ 4F44E - Formerly known as the CD4E.
^ 4F46S - Formerly known as the AX4S and regular-duty AXOD-E.
^ 4F50N - Formerly known as the AX4N and heavy-duty AXOD-E.
^ 4R44E - Formerly known as A4LD for 3.0L applications.
^ 4R55E - Formerly known as A4LD for 4.0L applications.
^ 4R70W - Formerly known as AOD-E.
^ 4R100 - Formerly known as E4OD.
^ 5R44E - Formerly known as A5LD for 3.0L applications.
^ 5R55E - Formerly known as A5LD for 4.0L applications.
^ 5R55N - Lincoln LS automatic transmission.
^ 5R55W - Wide-ratio truck transmission.
^ 4x4L - 4x4 Low.
^ A/T - Automatic Transmission.
^ CCS - Coast Clutch Solenoid.
^ CCSF - Coast Clutch Solenoid Fault. Displays a YES if fault exists.
^ EPC - Electronic Pressure Control.
^ EPCV - Electronic Pressure Control Volts.
^ ESS - Electronic Shift Scheduling.
^ HCDSS - High Clutch Drum Speed Sensor. PCM input from the 4R44E and 4R55E.
^ M5OD - Manual 5-Speed transmission with overdrive (RWD).
^ M/T - Manual Transmission/Transaxle.
^ NPS - Neutral Pressure Switch or its signal input to the PCM.
^ OCS - Overdrive Cancel Switch.
^ OSS - Output Shaft Speed. Indicates rotational speed of the transmission output shaft.
^ PNP - Park/Neutral Position switch. Also known as Neutral Drive Switch (NDS), Neutral Gear Switch (NGS), and Transmission Switch Neutral (TSN).
^ REVERSE or REV - Transmission Reverse Switch Input.
^ SIL - Shift Indicator Lamp. A lamp that indicates the preferred shift points on select manual transmission/transaxle vehicles.
^ SS1/SS2/SS3 - Shift solenoids. Devices that control the shifting in an automatic transmission.
^ TCC - 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.
^ Torque converter - A device which by its design multiplies the torque in a fluid coupling between an engine and transmission/transaxle.
^ TFT - Transmission Fluid Temperature. Indicates temperature of transmission fluid.
^ Transaxle - A device consisting of a transmission and axle drive gears assembled in the same case. Front-wheel drive applications.
^ Transmission - A device which selectively increases or decreases the ratio of relative rotation between its input and output shafts. Rear-wheel drive applications.
^ TR - Transmission Range. The range in which the transmission is operating.
^ TR Sensor - Formerly known as Manual Lever Position Sensor (MLPS). Provides information to the PCM on the transmission range selector position.
^ TR V - Transmission Range Voltage.
^ TSS - Turbine Shaft Speed. Indicates rotational speed of the transmission turbine shaft.
^ VSS - Vehicle Speed Sensor. A magnetic pickup device that generates an AC signal that is proportional to vehicle speed.