Powertrain Control Hardware

POWERTRAIN CONTROL HARDWARE

Powertrain Control Module (PCM)

Vehicle PCM Application Table:

The center of the electronic engine control (EEC) system is a microprocessor called the PCM. The PCM receives input from sensors and other electronic components (switches, relays). Based on the information received and programmed into its memory, the PCM generates output signals to control various relays, solenoids and actuators. There are several different types of PCMs in use for this model year. Refer to the Vehicle PCM Application Table for PCM types and their applications.

PCM Locations

104-Pin PCM:

104-PIN PCM Power And Grounds:

140-Pin PCM:

140-PIN PCM Power And Grounds (Part 1):

140-PIN PCM Power And Grounds (Part 2):

150-Pin PCM:

150-PIN PCM Power And Grounds (Part 1):

150-PIN PCM Power And Grounds (Part 2):

170-Pin PCM:

170-PIN PCM Power And Grounds:

190-Pin PCM:

190-PIN PCM Power And Grounds (Part 1):

190-PIN PCM Power And Grounds (Part 2):

For PCM removal and installation procedures, refer to Computers and Control Systems, Electronic Engine Controls.
- Focus - passenger side behind the kickpanel
- Five Hundred, Freestyle, Montego - engine compartment, passenger side, mounted to the cowl.
- Fusion, Milan, MKZ - engine compartment, driver side, under battery, mounted to the cowl.
- Taurus, Freestar, Monterey - (access from the engine compartment) on the passenger side.
- Mustang - front of engine compartment, passenger side, near fender, under the battery junction box (BJB).
- Crown Victoria, Grand Marquis, Town Car - engine compartment, driver side, fender mounted.
- Explorer, Explorer Sport Trac, Mountaineer - passenger side, near side cowl, behind the glove compartment.
- Escape, Mariner, Ranger - behind the instrument panel (cowl), center to both driver and passenger sides (access from the engine compartment).
- Edge, Expedition, Mark LT, MKX, Navigator, F-Series, F-Super Duty - passenger side of the engine compartment, mounted to the cowl.
- E-Series - engine compartment, driver side, near the cowl (access from the engine compartment).

Fuel Pump Driver Module (FPDM)

NOTE: The Mustang 5.4L uses 2 FPDMs to control fuel for the fuel delivery system. The PCM outputs only one fuel pump duty cycle on the fuel pump control (FPC) circuit. This circuit is used by both FPDMs. The PCM individually monitors the FPDMs through the fuel pump monitor (FPM) and FPM2 circuits. The FPDM located on the driver side of the luggage compartment is referred to as FPDM and the FPDM located on the passenger side of the luggage compartment, is referred to as FPDM2.

The FPDM receives a duty cycle signal from the PCM and controls the fuel pump operation in relation to this duty cycle. This results in variable speed fuel pump operation. The FPDM sends diagnostic information to the PCM on the fuel pump monitor circuit.

Keep Alive Memory (KAM)
The PCM stores information in KAM (a memory integrated circuit chip) about vehicle operating conditions and then uses this information to compensate for component variability. The KAM remains powered when the key is in the OFF position so that this information is not lost.

Hardware Limited Operation Strategy (HLOS)
This system of special circuitry provides minimal engine operation should the PCM (mainly the central processing unit [CPU] or EEPROM) stop functioning correctly. All modes of self-test are not functional at this time. Electronic hardware is in control of the system while in HLOS.

HLOS Allowable Output Functions:
- spark output controlled directly by the crankshaft position (CKP) signal
- fixed fuel pulse width synchronized with the CKP signal
- fuel pump relay energized
- idle speed control output signal functional

HLOS Disabled Outputs To Default State:
- exhaust gas recirculation (EGR) solenoids
- no torque converter clutch lock-up

Integrated Electronic Ignition System
The integrated electronic ignition system consists of a CKP sensor, coil pack(s), connecting wiring, and PCM. The coil on plug (COP) integrated electronic ignition system uses a separate coil for each spark plug and each coil is mounted directly onto the plug. The COP integrated electronic ignition system eliminates the need for spark plug wires but does require input from the camshaft position (CMP) sensor.

Power and Ground Signals

Electronic Throttle Control Reference Voltage (ETCREF)
ETCREF is a consistent positive voltage (5.0 volts ± 0.5) supplied by the PCM. ETCREF is internally bussed within the PCM and is specifically dedicated to the accelerator pedal position (APP) sensor and the electronic throttle body (ETB) throttle position (TP) sensor.

Electronic Throttle Control Return (ETCRTN)
ETCRTN is a return path for ETCREF and is internally bussed within the PCM. ETCRTN is specifically dedicated to the APP sensor and the ETB TP sensor.

Gold Plated Pins

NOTE: Gold plated terminals should only be replaced with new gold plated terminals.

Some engine control hardware has gold plated pins within the connectors and mating harness connectors to improve electrical stability for low current draw circuits and to enhance corrosion resistance. The electronic engine control (EEC) components equipped with gold terminals vary by vehicle application.

Keep Alive Power (KAPWR)
KAPWR provides a constant voltage input independent of ignition switch state to the PCM. This voltage is used by the PCM to maintain the keep alive memory (KAM).

Mass Air Flow (MAF) Return
The mass air flow return (MAF RTN) is a dedicated analog signal return from the MAF sensor. It serves as a ground offset for the analog voltage differential input by the MAF sensor to the PCM.

Power Ground (PWR GND)
The PWR GND circuit(s) is directly connected to the battery negative terminal. PWR GND provides a return path for the PCM vehicle power (VPWR) circuits.

Signal Return (SIG RTN)
SIG RTN is a dedicated return path for VREF applied components.

Variable Reluctance Sensor Return (VRSRTN)
The VRSRTN circuit is a dedicated return path for variable reluctance (VR) type sensors.

Vehicle Buffered Power (VBPWR)
VBPWR is a regulated voltage supplied by the PCM to vehicle sensors. These sensors require a constant 12 volts for operation and cannot withstand VPWR voltage variations. VBPWR is regulated to VPWR minus 1.5 volts and is also current limited to protect the sensors.

Vehicle Power (VPWR)
VPWR is the primary source of PCM power. VPWR is switched through the EEC power relay and is controlled by the ignition switch.

Vehicle Reference Voltage (VREF)
VREF is a consistent positive voltage (5.0 volts ± 0.5) provided by the PCM. VREF is typically used by 3-wire sensors and some digital input signals.