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.
NA: Naturally Aspirated. 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. Gases 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 PCM input and output control signals.
On-Demand Test: The KOEO and KOER tests of the PCM initialized by a technician.
OC: Oxidation Catalytic converter. A catalytic converter system that reduces levels of HC and CO emissions.
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.
OSC: Output State Control.
OSS: Output Shaft Speed.
OTM: Output Test Mode
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 Lamp.
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 Electronic Engine Control (EEC) 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 the 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 - Gauge: The amount by which absolute pressure exceeds the 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.
PSPT: Power Steering Pressure Transducer
PTEC: PowerTrain Electronic Controller.
PTO: Power Take-Off.
PTOIL: Power Take-Off Indicator Lamp
PTO LOAD: Power Take-Off Load
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.
RDI: Restraint Deployment Indicator
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 of less than 1000 RPM to improve idle quality and improve emissions.
RF: Radio Frequency.
RFI: Radio Frequency Interference.
RFS: Returnless Fuel System.
RLC: Reverse Lamp Control
RM: Relay Module. A module containing 2 or more relays.
ROM: Read-Only Memory. Computer memory that can be accessed and used, 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.
SAIR: Secondary Air.
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. Identifies whether a fault exists in the Supercharger Bypass circuit.
SCCS: Speed Control Command Switch
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 the circuit termination is 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 closed-loop operation.
SIG RTN: Signal Return. A dedicated sensor ground circuit that is common to 2 or more sensors.
SIL: Shift Indicator Lamp.
Smart Driver: A PCM output driver that can detect faults (open or shorts) on its output circuit.
SME: Society of Manufacturing Engineers.
SMR: Starter Motor Request. An input signal provide to the PCM when the ignition switch is in the START position.
SOF: Shift-On-the-Fly.
SOHC: Single Overhead Cam.
Solenoid: A device consisting of an electrical coil which produces a magnetic field which changes the position of a metal plunger.
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.
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.
Tear Tag: The 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.
TP: Throttle Position sensor. A potentiometer that provides throttle angle and rate information for the PCM.
TP V: Throttle Position Sensor Voltage.
TP1: Throttle Position 1
TP2: Throttle Position 2
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 technician of any known vehicle concerns, procedures, or general repair 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, VCT1, VCT2: 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. 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 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 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, character F indicates front transaxle, 27 represents 270 ft/lbs of torque capacity and the character E represents an electronic shift.
- 4x4L: 4x4 Low.
- A/T: Automatic Transmission.
- CCS: Coast Clutch Solenoid.
- CCSF: Coast Clutch Solenoid Fault. Displays a YES if fault exists.
- EPC, EPC1, EPC2: 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.
- ISS: Intermediate/Input Shaft Speed Sensor.
- 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.
- 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 a 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.
- 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 the temperature of transmission fluid.
- Transaxle: A device consisting of a transmission and axle drive gears assembled in the same case. Front-wheel drive and some all-wheel 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, TR1, TR2, TR3, TR4: Transmission Range. The range in which the transmission is operating.
- TR Sensor: Provides information to the PCM on the transmission range selector position.
- TR V: Transmission Range Voltage.
- TRO-N: Transmission Range Output Neutral
- TRO-P: Transmission Range Output Park
- TS1: Transmission Range Sensor - 1st
- TSD: Transmission Range Sensor - Drive
- TSR: Transmission Range Sensor - Reverse
- 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.
- VSOUT: Vehicle Speed Output. A pulse width modulated vehicle speed signal.