Engine Controls - Introduction (except Diesel & Hybrid)

Note. The descriptions and specifications contained in this article were in effect at the time this article was approved for publication.

Important Safety Notice

Appropriate repair methods and procedures are essential for the safe, reliable operation of all motor vehicles, as well as the personal safety of the individual doing the work. This article provides general directions for repairing vehicles with tested, effective techniques. Following them helps to establish reliability.

There are numerous variations in procedures, techniques, tools, and parts for repairing vehicles, as well as in the skill of the individual doing the work. This article cannot possibly anticipate all such variations and provide advice or cautions as to each. Accordingly, anyone who departs from the instructions provided in this article must first establish that they compromise neither their personal safety nor the vehicle integrity by their choice of methods, tools, or parts.

Notes, Cautions, and Warnings

As you read through the procedures, NOTES, CAUTIONS, and WARNINGS are found throughout the publication. Each one is there for a specific purpose. NOTES give added information that help to complete a particular procedure. CAUTIONS are given to prevent making errors that could damage the vehicle. WARNINGS are to remind the technician to be especially careful in those areas where carelessness may cause personal injury. The following list contains some general WARNINGS that should be followed when working on a vehicle.

Always wear safety glasses for eye protection.
Use safety stands whenever a procedure requires working under the vehicle.
Make sure that the key is always in the OFF position, unless otherwise required by the procedure.
Set the parking brake when working on the vehicle. If the vehicle is equipped with an automatic transmission, place the gear selector in PARK unless otherwise instructed for a specific operation. If the vehicle is equipped with a manual transmission, the gear selector should be in REVERSE (engine OFF) or NEUTRAL (engine ON) unless instructed otherwise for a specific operation. Place wood blocks (4 inch x 4 inch or larger) against the front and rear surfaces of the tires to help prevent the vehicle from moving.
Operate the engine in a well-ventilated area to avoid the danger of carbon monoxide poisoning.
Keep yourself and your clothing away from moving parts when the engine is running, especially the drive belts.
To prevent serious burns, avoid contact with hot metal parts such as the radiator, exhaust manifold(s), tail pipe(s), three-way catalytic converter(s), and muffler(s).
Do not smoke while working on a vehicle.
To avoid injury, always remove rings, watches, loose hanging jewelry, and loose clothing before beginning work on a vehicle.
When it is necessary to work under the hood, keep hands and other objects clear of the radiator fan blades.

Preface

This article provides a step-by-step approach for diagnosing driveability, emission, and powertrain control system symptoms. Before beginning diagnosis, it may be helpful to reference any Technical Service Bulletins (TSBs) when available.

Note. For the diesel engines, refer to INTRODUCTION -- 6.0L DIESEL . For the Escape Hybrid or Mariner Hybrid, refer to INTRODUCTION - ESCAPE HYBRID & MARINER HYBRID .

This article is used in conjunction with the service information articles and SYSTEM WIRING DIAGRAMS . The service information articles are used to provide additional diagnostic or component removal and installation information. Refer to the appropriate SYSTEM WIRING DIAGRAMS article for vehicle specific wiring information and component, connector, and splice locations.

The following is a description of the information contained in each of the ENGINE PERFORMANCE articles.

Description and Operation

This article contains description and operation information on powertrain control systems and components and provides the technician with a general knowledge of the powertrain control system. Use this article when general information about the powertrain control system is desired.

Diagnostic Methods

This article contains information on specific diagnostic tasks that are used during diagnosis. Descriptions of specific diagnostic methods are included, as well as detailed instructions on how to access or carry out the task.

Symptom Charts

All diagnosis begins in the SYMPTOM CHARTS article with QT Step 1: Powertrain Control Module (PCM) Quick Test. If the PCM Quick Test is completed and no diagnostic trouble codes (DTCs) are retrieved, the technician is directed to Step 2: No Diagnostic Trouble Codes (DTCs) Present Symptom Chart Index. The No Diagnostic Trouble Codes (DTCs) Present Symptom Chart Index contains the list of symptoms addressed and directs the technician to the appropriate Step 3: No Diagnostic Trouble Codes (DTCs) Present Symptom Chart. If no PCM DTCs are present and the vehicle symptom is not listed in Step 2: No Diagnostic Trouble Codes (DTCs) Present Symptom Chart Index, the technician should go to the appropriate service information article to continue diagnosis.

Powertrain Diagnostic Trouble Code (DTC) Charts and Descriptions

This article contains the Diagnostic Trouble Code (DTC) Charts and Descriptions. These charts and descriptions are referenced if a DTC is retrieved in the SYMPTOM CHARTS article. Also included are the list of possible causes and diagnostic aids.

Pinpoint Tests

All pinpoint tests are included. Never enter a pinpoint test unless directed there. When directed to a pinpoint test, always read the information included at the beginning of the pinpoint test.

Reference Values

This article contains the Typical Diagnostic Reference Values charts. The technician is directed to these charts from Pinpoint Test Z in the PINPOINT TESTS article.

How to Use the Diagnostic Procedures

Use the information about the vehicle driveability or emission concerns to attempt to verify/recreate the symptom. Look for any vehicle modifications or aftermarket items that may contribute to the symptom. A check of any applicable TSBs may be useful if this information is available.
Go to the «SYMPTOM CHARTS»(/lincoln/mark-lt/i-2005-2009/remont/testing-diagnostics/#engine-controls-symptom-charts-except-diesel-hybrid) article, QT Step 1: Powertrain Control Module (PCM) Quick Test. Carry out the PCM quick test steps. Follow any notes as directed.
If the PCM quick test is completed, no DTCs were retrieved, and no special notes applied, go to Step 2: No Diagnostic Trouble Codes (DTCs) Present Symptom Chart Index.
Select the symptom that best describes the vehicle symptom (for multiple symptoms select the one that is most evident). Go to Step 3: No Diagnostic Trouble Codes (DTCs) Present Symptom Chart that is indicated. If no PCM DTCs are present and the vehicle symptom is not listed in the No Diagnostic Trouble Codes (DTCs) Present Symptom Chart Index, go to the appropriate service information article to continue diagnosis.
The No Diagnostic Trouble Codes (DTCs) Present Symptom Charts contain areas to be tested for diagnosis of the vehicle symptom. The chart is arranged to place the higher probability or easiest to test items toward the top of the chart. However, the technician is not required to follow this order due to reasons such as variations in vehicle type, vehicle repair history, or technician experience. The System/Component column indicates the areas that are tested. This column may also contain a quick system/component test. The Reference column indicates where to go for the System/Component testing. All references are to the beginning of a pinpoint test in the «PINPOINT TESTS»(/lincoln/mark-lt/i-2005-2009/remont/testing-diagnostics/#engine-controls-pinpoint-tests-except-diesel-hybrid) article unless noted otherwise. If referred to a pinpoint test or a service information article , go to the procedures. Follow the directions given in those procedures, including directions to other tests or articles. If a damaged part is found, repair as directed. If no concern is found, and diagnosis in that area is complete, return to the No Diagnostic Trouble Codes (DTCs) Present Symptom Chart and continue to the next item. If a quick system/component test is in the System/Component column, the Reference column indicates where to go if the test failed.
During diagnosis, if directed to test a system/component that is not contained on that vehicle, go to the next step.
If the No Diagnostic Trouble Codes (DTCs) Present Symptom Chart for the vehicle symptom is completed and no concern is found, return to Step 2: No Diagnostic Trouble Codes (DTCs) Present Symptom Chart Index to address the next most prominent symptom. If all diagnosis is complete and no concern is found, it may be helpful to refer to «PINPOINT TEST Z - INTERMITTENT»(/lincoln/mark-lt/i-2005-2009/remont/testing-diagnostics/#engine-controls-pinpoint-tests-except-diesel-hybrid) to continue diagnosis.
The installation of any new component that affects the PCM adaptive learning strategies (adaptive airflow, idle speed, refueling event, or fuel trim) requires the reset of keep alive memory (KAM). Refer to «RESETTING THE KEEP ALIVE MEMORY (KAM)»(/lincoln/mark-lt/i-2005-2009/remont/testing-diagnostics/#engine-controls-diagnostic-methods-except-diesel-hybrid) .
After any repair, reconnect any components and remove any test equipment. Verify that the vehicle is operating correctly and the original complaint is no longer present. If a DTC was present, clear the DTCs and repeat the self-test to verify the repair.
If a symptom is determined to be intermittent, a careful visual and physical underhood inspection of connectors, wiring harnesses, vacuum lines, and components is required. The Customer Information Worksheet may contain more detailed symptom information. Before an in-depth diagnosis begins, start the engine and wiggle wires, tap on components while listening for an indication of a concern (such as an RPM change or a relay clicking).

Information about engine conditions is stored when a DTC that illuminates the malfunction indicator lamp (MIL) is set. This information is called freeze frame data and may be helpful in diagnosing intermittent concerns. Refer to FREEZE FRAME DATA for more information.

What's New

The following is a list of changes to the service information for 2007

New Vehicles

Edge with new 3.5L 4V engine
Explorer Sport Trac
MKX with new 3.5L 4V engine
MKZ with new 3.5L 4V engine

Deleted Vehicles

Ford GT
Lincoln LS
Zephyr

Other Changes

Computer-controlled shutdown feature for equipped vehicles
Crown Victoria, Grand Marquis, Town Car and Ranger equipped with new 170-pin PCM
Expedition/Navigator equipped with a mechanical returnless fuel system (MRFS)
Mustang with new 5.4L supercharged engine

Acronyms and Definitions

Note. 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 ENGINE PERFORMANCE article or consult the service information article for the specific vehicle being repaired.

2V: Two valves per engine cylinder
3V: Three valves per engine cylinder
4V: Four valves per engine cylinder
4WD: Four Wheel Drive
ABS: Anti-lock Brake System
A/C: Air Conditioning
A/CC: Air Conditioning Clutch
A/CCR: Air Conditioning Clutch Control Relay
ACCS: Air Conditioning Cycling Switch
ACDS: Air Conditioning Diagnostic Switch (refrigerant containment switch)
ACET: Air Conditioning Evaporator Temperature
ACP: Air Conditioning Pressure
ACPSW: Air Conditioning Pressure Switch
A/D: Analog-to-Digital. Analog-to-Digital signal conversion.
AIR: Secondary Air Injection
APP: Accelerator Pedal Position
BARO: Barometric Pressure
BJB: Battery Junction Box
BPP: Brake Pedal Position
BPS: Brake Pedal Switch
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.
CAC: Charge Air Cooler. A device which lowers the temperature of pressurized intake air.
CAN: Controller Area Network
CCM: Comprehensive Component Monitor
CF: Cooling Fan
CHT: Cylinder Head Temperature
CKP: Crankshaft Position
CL: Closed Loop. An operating condition or mode which enables operation based on sensor feedback.
CMCV: Charge Motion Control Valve
CMP: Camshaft Position
CO: Carbon Monoxide. A colorless, odorless, and toxic gas that is a component of auto exhaust emissions.
CO 2 : Carbon Dioxide. A colorless, odorless gas that is a normal by-product of the combustion of fuel.
COP: Coil On Plug. Ignition coil on plug assembly.
CPP: Clutch Pedal Position
CPR: Cardiopulmonary Resuscitation
CPU: Central Processing Unit
CTO: Clean Tach Output. Signal used to drive the instrument panel tachometer.
CV: Canister Vent Solenoid. A solenoid which seals the evaporative emission (EVAP) system from the atmosphere during the EVAP monitor test.
CVT: Continuously Variable Transmission
DBA: Driver Brake Application
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.
DEPS: Dual Equal Phase Shifting
DIPS: Dual Independent Phase Shifting
DLC: Data Link Connector. SAE standard J1962 connector providing access to vehicle diagnostic information.
DMM: Digital Multimeter
DRI: Deposit Resistant Injector
DTM: Diagnostic Test Mode. A level of capability in an OBD system.
DTC: Diagnostic Trouble Code. An alpha/numeric identifier for a concern identified by the OBD system.
E10: Fuel containing 10% ethanol
E85: Fuel containing 85% ethanol
EATC: Electronic Automatic Temperature Control
ECM: Electronic Control Module
ECT: Engine Coolant Temperature
EEC: Electronic Engine Control
EEGR: Electric Exhaust Gas Recirculation System
EEPROM: Electrically Erasable Programmable Read-Only Memory. An electronic component in the PCM that allows the electronic storage of information.
EGR: Exhaust Gas Recirculation. A process in which a small amount of exhaust gas is routed into the combustion chamber.
EI: Electronic Ignition. An electronic ignition system that has the ignition control module integrated into the PCM.
EMD: Engine Manufacturers Diagnostics
EMI: Electromagnetic Interference. Usually caused by ignition voltage spikes, solenoids, relay operation, or noisy generator contacts.
EONV: Engine Off Natural Vacuum
EOT: Engine Oil Temperature
EPS: Exhaust Phase Shifting
E-Quizzer: Enhanced Quizzer
ERFS: Electronic Returnless Fuel System
ESM: EGR System Module
ESOF: Electronic Shift-on-the-Fly
ETB: Electronic Throttle Body
ETBTACM: Electronic Throttle Body Throttle Actuator Control Motor
ETBTPS: Electronic Throttle Body Throttle Position Sensor
ETC: Electronic Throttle Control
ETCREF: Electronic Throttle Control Reference Voltage. 5V for ETC (APP VREF, TP VREF).
ETCRTN: Electronic Throttle Control Return
EVAPCP: Evaporative Canister Purge Valve. A valve which controls the venting of fuel vapor from the evaporative emissions canister into the intake manifold for combustion.
FAOS: Fore-Aft Oxygen Sensor
FC: Fan Control
FCIL: Fuel Cap Indicator Lamp. Indicates that the fuel filler cap is not correctly installed.
FEPS: Flash EEPROM Programming Signal. An 18-volt DC signal input from the scan tool used by the PCM to initiate programming.
FFV: Flexible Fuel Vehicle
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.
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.
FPM: Fuel Pump Monitor
FRP: Fuel Rail Pressure
FRPT: Fuel Rail Pressure Temperature
FSS: Fan Speed Sensor
FTP: Fuel Tank Pressure
FWD: Front Wheel Drive
GND: Ground
GPM: 1. Grams per Mile. 2. Gallons per Minute.
H: Hydrogen
HC: 1. Hydrocarbon. A by-product of combustion and a component of auto exhaust emissions. 2. High Compression.
HDR: High Data Rate
HFC: High Fan Control
HLOS: Hardware Limited Operating Strategy. A mode of operation where the PCM uses fixed values in response to internal PCM concerns in place of output commands.
HO2S: Heated Oxygen Sensor. Provides information on rich or lean exhaust conditions to the PCM.
Hz: Hertz. Cycles per second.
IAC: Idle Air Control. Electrical control of throttle bypass air.
IAT: Intake Air Temperature
IAT2: Intake Air Temperature 2. Used on supercharged vehicles.
IC: Integrated Circuit. A small semi-conductor device capable of many separate circuit functions.
IDM: Ignition Diagnostic Monitor
IFS: Inertia Fuel Shut-Off
I/M: Inspection/Maintenance
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 concerns.
IMTV: Intake Manifold Tuning Valve. Controls airflow through runners in a split intake manifold.
INJ: Injector
IPC: Independent Plausibility Checker
IPS: Intake Phase Shifting
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. 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 (in-Hg).
KS: Knock Sensor
L: Liters. The unit of volume in the metric measuring system. One liter equals 1.06 quarts.
LCM: Lighting Control Module
LDR: Low Data Rate
LFC: Low Fan Control
LONGFT: Long-Term Fuel Trim. Fuel flow adjustment determined by the PCM.
LOS: Limited Operating Strategy
LSRC: Long Short Runner Control
MAF: Mass Air Flow
MAP: Manifold Absolute Pressure. The internal pressure of the intake manifold.
MFC: Medium Fan Control
MFF: Misfire Freeze Frame
MIL: Malfunction Indicator Lamp. An indicator lamp alerting the driver of an emission related concern.
MRFS: Mechanical Returnless Fuel System
MSOF: Manual Shift-on-the-Fly
N: Nitrogen
NMOG: Non-Methane Organic Gases
NO X : Oxides of Nitrogen. Gasses formed at high combustion temperatures.
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.
OSC: Output State Control
OSR: On-Board System Readiness
OTM: Output Test Mode
PATS: Passive Anti-Theft System
PCM: Powertrain Control Module. Formerly known as the electronic engine control (EEC) processor.
PCM-VSO: Powertrain Control Module - Vehicle Speed Output
PCV: Positive Crankcase Ventilation. A system which allows the controlled flow of crankcase vapors into the combustion chamber.
PCVTE: Positive Crankcase Ventilation Thermal Extension
Pd: Palladium
PDJB: Power Distribution Junction Box
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.
PS: Pressure Switch
PSP: Power Steering Pressure. Indicates the pressure in the power steering system.
PSPT: Power Steering Pressure Transducer
Pt: Platinum
PTO: Power Take-Off
PTS: Professional Technician Society
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.
RAM: Random Access Memory. Memory into which information can be written as well as read.
RFI: Radio Frequency Interference
Rh: Rhodium
ROM: Read-Only Memory. Computer memory that can be accessed and used, but not altered.
RPM: Revolutions Per Minute
RWD: Rear Wheel Drive
SAE: Society of Automotive Engineers
SCB: Supercharger Bypass
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.
SJB: Smart Junction Box
SMR: Starter Motor Request
TAC: Throttle Actuator Control
TACM: Throttle Actuator Control Motor
TCM: Transmission Control Module
TCSS: Transfer Case Speed Sensor
TDC: Top Dead Center
TP: Throttle Position
TPPC: Throttle Plate Position Controller
TSB: Technical Service Bulletin. Notifies technician of any known vehicle concerns, procedures, or general repair information.
TWC: Three-Way Catalytic
VBPWR: Vehicle Buffered Power. A PCM-supplied power source that supplies regulated voltage.
VCM: Vehicle Communication Module
VCT: Variable Camshaft Timing
VECI: Vehicle Emission Control Information
VID: Vehicle Identification
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.
VPWR: Vehicle Power. A switched circuit that provides power to the EEC system. Compare to battery voltage (B+).
VR: Variable Reluctance
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 Air Conditioning Cutoff
WDS: Worldwide Diagnostic System
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: 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: 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.

Engine Controls - Introduction (except Diesel & Hybrid) Lincoln Mark LT I