Engine system DODGE RAM 2003 Service Manual PDF

(10) Remove the heater hose coolant return tube
mounting bolt (Fig. 54) (Fig. 55) and remove the tube
from the engine. Discard the old tube O-ring.
(11) Remove the bracket-to-intake manifold bolts
(number 1 and 2 (Fig. 52).(12) Remove the remaining bracket-to-engine bolts
(Fig. 55).
(13) Lift and position the generator and A/C com-
pressor (along with their common mounting bracket)
to gain access to the bypass hose. A block of wood
may be used to hold the assembly in position.
(14) Loosen and position both hose clamps to the
center of the bypass hose. A special clamp tool must
be used to remove the constant tension clamps.
Remove the hose from the vehicle.
REMOVAL - WATER PUMP BYPASS HOSE
WITHOUT AIR CONDITIONING
A water pump bypass hose (Fig. 56) is used
between the intake manifold and water pump on all
gas powered engines. To test for leaks, (Refer to 7 -
COOLING - DIAGNOSIS AND TESTING).
(1) Partially drain the cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE). Do not
waste reusable coolant. If the solution is clean, drain
the coolant into a clean container for reuse.
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP. ALWAYS WEAR SAFETY GLASSES WHEN
SERVICING CONSTANT TENSION CLAMPS.
Fig. 53 Idler Pulley - 5.9L V-8 Gas Engine
Fig. 54 Coolant Return
1 - COOLANT RETURN TUBE
2 - WATER PUMP
3 - TUBE MOUNTING BOLT
4 - O-RING
Fig. 55 Bracket Bolts - 5.9L V-8 Gas
1 - COOLANT TUBE MOUNTING BOLT
2 - BRACKET MOUNTING BOLTS
DRENGINE 7 - 69
WATER PUMP INLET TUBE - 5.9L (Continued)

CAUTION: A number or letter is stamped into the
tongue of the constant tension clamps. If replace-
ment is necessary, use only an original equipment
clamp with a matching number or letter and width.
(2) Loosen both of the bypass hose clamps and
position them to the center of the hose.
(3) Removethe hose from the vehicle.
INSTALLATION
INSTALLATION - WATER PUMP BYPASS HOSE
WITH AIR CONDITIONING
(1) Position the bypass hose clamps to the center
of the bypass hose.
(2) Install the bypass hose to the engine.
(3) Secure both of the hose clamps.
(4) Install the generator-A/C mounting bracket
assembly to the engine. Tighten bolt number 1 (Fig.
53) to 41 N´m (30 ft. lbs.). Tighten bolt number 2
(Fig. 53) to 28 N´m (20 ft. lbs.). Tighten bracket
mounting bolts (Fig. 53) (Fig. 53) to 40 N´m (30 ft.
lbs.).
(5) Install a new O-ring to the heater hose coolant
return tube. Coat the new O-ring with antifreeze
before installation.
(6) Install the coolant return tube and its mount-
ing bolt to the engine.
(7) Connect the throttle body control cables.
(8) Install the oil dipstick mounting bolt.
(9) Install the idler pulley. Tighten the bolt to 41
N´m (30 ft. lbs.) (Fig. 57).
(10) Install the drive belt (Refer to 7 - COOLING/
ACCESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION).CAUTION: When installing the serpentine accessory
drive belt, the belt must be routed correctly. If not,
the engine may overheat due to the water pump
rotating in the wrong direction (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION). The correct belt with the correct length must
be used.
(11) Install the air cleaner assembly.
(12) Install the upper radiator hose to the radiator.
(13) Connect the throttle cable to the clip at the
radiator fan shroud.
(14) Connect the wiring harness to the A/C com-
pressor.
(15) Fill the cooling system (Refer to 7 - COOLING
- STANDARD PROCEDURE).
(16) Start and warm the engine. Check for leaks.
INSTALLATION - WATER PUMP BYPASS HOSE
WITHOUT AIR CONDITIONING
(1) Position the bypass hose clamps to the center
of the bypass hose.
(2) Install the bypass hose tothe engine.
(3) Secure both of the hose clamps.
(4) Fill the cooling system (Refer to 7 - COOLING
- STANDARD PROCEDURE).
(5) Start and warm the engine. Check for leaks.
WATER PUMP - 5.7L
REMOVAL
(1) Disconnect negative battery cable.
(2) Drain coolant.
(3) Remove serpentine belt.
(4) Remove fan clutch assembly.
(5) Remove coolant fill bottle.
Fig. 56 Water Pump Bypass Hose - Typical
1 - WATER PUMP BYPASS HOSE
2 - FAN BLADE ASSEMBLY
3 - VISCOUS FAN DRIVE
4 - WATER PUMP AND PULLEY
Fig. 57 Tensioner Mounting
1 - DOWEL PIN HOLE
2 - TENSIONER MOUNTING BRACKET
7 - 70 ENGINEDR
WATER PUMP INLET TUBE - 5.9L (Continued)

(6) Disconnect washer bottle wiring and hose.
(7) Remove fan shroud assembly.
(8) Remove A/C compressor and genterator brace.
(9) Remove idler pulleys.
(10) Remove belt tensioner assembly.
(11) Remove upper and lower radiator hoses.
(12) Remove heater hoses.
(13) Remove water pump mounting bolts and
remove pump.INSTALLATION
(1) Install water pump and mounting bolts.
Tighten moubting bolts to 24 N´m (18 ft. lbs.).
(2) Install heater hoses.
(3) Install upper and lower radiator hoses.
(4) Install belt tensioner assembly.
(5) Install idler pulleys.
(6) Install A/C compressor and alternator brace.
Tighten bolt and nuts to 28 N´m (21 ft. lbs.).
(7) Install fan shroud assembly.
(8) Connect washer bottle wiring and hose.
(9) Install coolant fill bottle.
(10) Install fan clutch assembly.
(11) Install serpentine belt.
(12) Connect negative battery cable.
(13) Fill coolant.
(14) Pressure test coolant system
DRENGINE 7 - 71
WATER PUMP - 5.7L (Continued)

ers are supplied as standard equipment on diesel
engine powered models when equipped with an auto-
matic transmission.
The main water-to-oil transmission oil cooler is
mounted to a bracket on the intake side of the engine
(Fig. 4).
The air-to-oil cooler is located in front of and to the
left side of the radiator (Fig. 5).
OPERATION
The transmission oil is routed through the main
cooler first, then the auxiliary cooler where addi-
tional heat is removed from the transmission oil
before returning to the transmission. The cooler has
an internal thermostat that controls fluid flow
through the cooler. When the transmission fluid is
cold (less then operating temperature), the fluid is
routed through the cooler bypass. When the trans-
mission fluid reaches operating temperatures and
above, the thermostat closes off the bypass allowing
fluid flow through the cooler. The thermostat is ser-
vicable.
REMOVAL
REMOVALÐAIR TO OIL COOLER
(1) Remove Charge Air Cooler (Refer to 11 -
EXHAUST SYSTEM/TURBOCHARGER SYSTEM/
CHARGE AIR COOLER AND PLUMBING -
REMOVAL).(2) Place a drain pan under the oil cooler.
(3) Raise the vehicle.
(4) Disconnect the oil cooler quick-connect fittings
from the transmission lines.
(5) Remove the charge air cooler-to-oil cooler bolt
(Fig. 6).
(6) Remove two mounting nuts.
(7) Remove the oil cooler and line assembly
towards the front of vehicle. Cooler must be rotated
and tilted into position while removing.
REMOVALÐWATER TO OIL COOLER
CAUTION: If a leak should occur in the water-to-oil
cooler mounted to the side of the engine block,
engine coolant may become mixed with transmis-
sion fluid. Transmission fluid may also enter engine
cooling system. Both cooling system and transmis-
sion should be drained and inspected in case of oil
cooler leakage.
(1) Disconnect both battery negative cables.
(2) Remove starter (Refer to 8 - ELECTRICAL/
STARTING/STARTER MOTOR - REMOVAL).
(3) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(4) Disconnect coolant lines from cooler.
Fig. 4 Transmission Water-To-Oil CoolerÐDiesel
EngineÐTypical
1 - TRANSMISSION WATER-TO-OIL COOLER
Fig. 5 Auxiliary Transmission Oil CoolerÐDiesel
Engine
1 - MOUNTING BOLTS
2 - RADIATOR
3 - QUICK-CONNECT FITTINGS
4 - TRANSMISSION OIL COOLER
7 - 74 TRANSMISSIONDR
TRANS COOLER - 5.9L DIESEL (Continued)

(5) Disconnect transmission oil lines from cooler.
Plug cooler lines to prevent oil leakage.
(6) Remove cooler bracket to transmission bolt.
(7) Remove two cooler bracket to cooler bolts.
(8) Remove cooler assembly from vehicle. (Fig. 7)
INSTALLATION
INSTALLATIONÐAIR TO OIL COOLER
(1) Carefully position the oil cooler assembly to the
vehicle.
(2) Install two nuts and one bolt. Tighten to 11
N´m (95 in. lbs.) torque.
(3) Connect the quick-connect fittings to the trans-
mission cooler lines.
(4) Install Charge Air Cooler (Refer to 11 -
EXHAUST SYSTEM/TURBOCHARGER SYSTEM/
CHARGE AIR COOLER AND PLUMBING -
INSTALLATION).
(5) Start the engine and check all fittings for
leaks.(6) Check the fluid level in the automatic trans-
mission (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 47RE/FLUID - STANDARD
PROCEDURE).
INSTALLATION
(1) Position oil cooler on cylinder block.
(2) Install two mounting bolts to cooler at the cyl-
inder block. Torque bolts to 77N´m (57 ft. lbs.)
(3) Install cooler bracket to transmission adapter
bolt. Tighten to 24N´M (18 ft. lbs.).
(4) Connect transmission oil lines to cooler.
(5) Connect coolant hoses to cooler.
(6) Install starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - INSTALLA-
TION).
(7) Connect battery negative cables.
(8) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(9) Check transmission oil level and fill as neces-
sary (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 47RE/FLUID - STANDARD
PROCEDURE).
Fig. 6 Auxiliary Transmission Oil CoolerÐDiesel
Engine
1 - MOUNTING BOLTS
2 - RADIATOR
3 - QUICK-CONNECT FITTINGS
4 - TRANSMISSION OIL COOLER
Fig. 7 Transmission Water-To- Oil CoolerÐDiesel
1 - TRANSMISSION WATER-TO-OIL COOLER
DRTRANSMISSION 7 - 75
TRANS COOLER - 5.9L DIESEL (Continued)

INSTALLATION
(1) Install antenna cable to radio.
(2) Connect electrical harness connector to radio.
(3) Install radio to instrument panel.
(4) Install instrument panel center bezel (Refer to
23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL CENTER BEZEL - INSTALLATION).
(5) Connect battery negative cable.
RADIO NOISE SUPPRESSION
GROUND STRAP
DESCRIPTION
Radio noise suppression devices are factory-in-
stalled standard equipment on this vehicle. Radio
Frequency Interference (RFI) and ElectroMagnetic
Interference (EMI) can be produced by any on-board
or external source of electromagnetic energy. These
electromagnetic energy sources can radiate electro-
magnetic signals through the air, or conduct them
through the vehicle electrical system.
When the audio system converts RFI or EMI to an
audible acoustic wave form, it is referred to as radio
noise. This undesirable radio noise is generally man-
ifested in the form of ªbuzzing,º ªhissing,º ªpopping,º
ªclicking,º ªcrackling,º and/or ªwhirringº sounds. In
most cases, RFI and EMI radio noise can be sup-
pressed using a combination of vehicle and compo-
nent grounding, filtering and shielding techniques.
This vehicle is equipped with factory-installed radio
noise suppression devices that were designed to min-
imize exposure to typical sources of RFI and EMI;
thereby, minimizing radio noise complaints.Factory-installed radio noise suppression is accom-
plished primarily through circuitry or devices that
are integral to the factory-installed radios, audio
power amplifiers and other on-board electrical com-
ponents such as generators, wiper motors, blower
motors, and fuel pumps that have been found to be
potential sources of RFI or EMI. External radio noise
suppression devices that are used on this vehicle to
control RFI or EMI, and can be serviced, include the
following:
²Engine-to-body ground strap- This length of
braided ground strap has an eyelet terminal connec-
tor crimped to each end. One end is secured to the
engine cylinder head(s). The other is secured to the
plenum at the exhaust heat shield forward/outer
attaching stud.
²Resistor-type spark plugs- This type of spark
plug has an internal resistor connected in series
between the spark plug terminal and the center elec-
trode to help reduce the production of electromag-
netic radiation that can result in radio noise.
OPERATION
There are two common strategies that can be used
to suppress Radio Frequency Interference (RFI) and
ElectroMagnetic Interference (EMI) radio noise. The
first suppression strategy involves preventing the
production of RFI and EMI electromagnetic signals
at their sources. The second suppression strategy
involves preventing the reception of RFI and EMI
electromagnetic signals by the audio system compo-
nents.
The use of braided ground straps in key locations
is part of the RFI and EMI prevention strategy.
These ground straps ensure adequate ground paths,
particularly for high current components such as
many of those found in the starting, charging, igni-
tion, engine control and transmission control sys-
tems. An insufficient ground path for any of these
high current components may result in radio noise
caused by induced voltages created as the high cur-
rent seeks alternative ground paths through compo-
nents or circuits intended for use by, or in close
proximity to the audio system components or circuits.
Preventing the reception of RFI and EMI is accom-
plished by ensuring that the audio system compo-
nents are correctly installed in the vehicle. Loose,
corroded or improperly soldered wire harness connec-
tions, improperly routed wiring and inadequate audio
system component grounding can all contribute to
the reception of RFI and EMI. A properly grounded
antenna body and radio chassis, as well as a shielded
antenna coaxial cable with clean and tight connec-
tions will each help reduce the potential for reception
of RFI and EMI.
Fig. 7 ANTENNA TO RADIO
1 - RADIO
2 - LOCKING ANTENNA CONNECTOR
3 - INSTRUMENT PANEL ANTENNA CABLE
8A - 8 AUDIODR
RADIO (Continued)

CHIME/BUZZER
TABLE OF CONTENTS
page page
CHIME/BUZZER
DESCRIPTION..........................1
OPERATION............................1DIAGNOSIS AND TESTING - CHIME
CONDITIONS..........................2
CHIME/BUZZER
DESCRIPTION
The chime module is located within the instrument
cluster and is not serviceable. The chime system pro-
vides the driver with warning chimes for:
²Air Bag
²Seat Belt
²Low Fuel
²Door Ajar
²Low Wash
²Park Brake
²Over Speed
²Turn Signal On
²Key-In Ignition
²Exterior Lamps ON
²Warning Lamp Announcement
²Transmission Over Temperature
OPERATION
FASTEN SEAT BELT
The seat belt reminder system uses both visual
and audible signals. The Instrument Cluster moni-
tors the driver seat belt buckle switch. When the
ignition switch transitions from OFF to RUN and the
driver seat belt has not been buckled, the Instrument
Cluster will illuminate the seat belt indicator lamp
and sound the chime. The system will always illumi-
nate the seat belt reminder lamp for four to eight
seconds when the ignition switch is turned to the ON
position. The CHIME will sound during the same
time interval if the driver's seat belt is not fastened.
The warning lamp will remain illuminated as long as
the seat belt remains unbuckled, and the ignition
switch is in the RUN position. Passenger seat belts
are not connected to the system.
HEADLAMPS REMINDER
The Instrument Cluster monitors the multiplex
headlamp switch. The headlamp audible warning will
alert the driver that the exterior lamps have been
left on. If the ignition switch is left off, the driver's
door open, and the headlamp switch is in the parklamp or headlamp position, the chime will sound
until the headlamp switch is turned off, the door is
closed or the battery protection time out expires.
KEY IN IGNITION REMINDER
The Instrument Cluster monitors the ignition
switch. The chime will activate if the drivers door is
opened and the key is in the ignition switch, with the
ignition switch in either the OFF, LOCK, or the
accessory (ACC) position. The chime will continue
until the key is removed from the ignition switch or
the door is closed.
DOOR AJAR CHIME
The Instrument Cluster monitors the door ajar
switches. A chime will sound once when the door is
opened, the ignition is in RUN position and vehicle
speed is present.
TURN SIGNAL ON
The Instrument Cluster monitors the multiplex
multifunction switch. The instrument cluster shall
remind the driver that either turn signal has been
left on by a continuous chime after the turn signal
indicator is left ON for 1.0 miles and the vehicle
speed is 15 mph or greater.
LOW FUEL REMINDER
When the fuel level drops to approximately 1/8
tank, the fuel symbol will light and a single chime
will sound. The light will remain on until fuel is
added.
OVER SPEED
During any ignition ON, the Instrument Cluster
maintains the most recently received speed. If the
vehicle speed exceeds a preprogramed limit set in the
instrument cluster it will activate a single chime.
WARNING LAMP ANNOUNCEMENT
The Instrument Cluster monitors critical engine
and transmission system parameters. If any of the
systems are out of their operating parameters, the
instrument cluster will illuminate a lamp and acti-
vate and audible chime.
DRCHIME/BUZZER 8B - 1

ELECTRONIC CONTROL MODULES
TABLE OF CONTENTS
page page
COMMUNICATION
DESCRIPTION..........................1
OPERATION............................2
CONTROLLER ANTILOCK BRAKE
DESCRIPTION..........................3
OPERATION............................3
REMOVAL.............................3
INSTALLATION..........................3
DATA LINK CONNECTOR
DESCRIPTION - DATA LINK CONNECTOR.....3
OPERATION - DATA LINK CONNECTOR......3
ENGINE CONTROL MODULE
DESCRIPTION - ECM.....................4
OPERATION - ECM......................4
REMOVAL.............................4
INSTALLATION..........................5
FRONT CONTROL MODULE
DESCRIPTION..........................5
OPERATION............................5
DIAGNOSIS AND TESTING - FRONT
CONTROL MODULE....................6
REMOVAL.............................6
INSTALLATION..........................6
HEATED SEAT MODULE
DESCRIPTION..........................6
OPERATION............................6
DIAGNOSIS AND TESTING - HEATED SEAT
MODULE.............................7
REMOVAL.............................7
INSTALLATION..........................7
POWERTRAIN CONTROL MODULE
DESCRIPTION
DESCRIPTION - PCM...................8DESCRIPTION - MODES OF OPERATION....8
DESCRIPTION - 5 VOLT SUPPLIES.......10
DESCRIPTION - IGNITION CIRCUIT SENSE . 10
DESCRIPTION - POWER GROUNDS......10
DESCRIPTION - SENSOR RETURN.......10
OPERATION
OPERATION - PCM....................11
OPERATION - 5 VOLT SUPPLIES.........11
OPERATION - IGNITION CIRCUIT SENSE . . . 12
REMOVAL.............................12
INSTALLATION.........................12
SENTRY KEY IMMOBILIZER MODULE
DESCRIPTION.........................13
OPERATION...........................13
STANDARD PROCEDURE - PCM/SKIM
PROGRAMMING......................14
REMOVAL.............................15
INSTALLATION.........................15
TRANSFER CASE CONTROL MODULE
DESCRIPTION.........................15
OPERATION...........................15
TRANSMISSION CONTROL MODULE
DESCRIPTION.........................19
OPERATION...........................19
STANDARD PROCEDURE
STANDARD PROCEDURE - TCM QUICK
LEARN..............................21
STANDARD PROCEDURE - DRIVE LEARN . . 21
COMMUNICATION
DESCRIPTION
The DaimlerChrysler Programmable Communica-
tion Interface (PCI) data bus system is a single wire
multiplex system used for vehicle communications on
many DaimlerChrysler Corporation vehicles. Multi-plexing is a system that enables the transmission of
several messages over a single channel or circuit. All
DaimlerChrysler vehicles use this principle for com-
munication between various microprocessor-based
electronic control modules. The PCI data bus exceeds
the Society of Automotive Engineers (SAE) J1850
Standard for Class B Multiplexing.
DRELECTRONIC CONTROL MODULES 8E - 1

ENGINE CONTROL MODULE
DESCRIPTION - ECM
The Engine Control Module (ECM) is bolted to the
left side of the engine below the intake manifold (Fig.
2).
OPERATION - ECM
The main function of the Engine Control Module
(ECM) is to electrically control the fuel system. The
Powertrain Control Module (PCM)does not control
the fuel system.
The ECM can adapt its programming to meet
changing operating conditions.If the ECM has
been replaced, flashed or re-calibrated, the
ECM must learn the Accelerator Pedal Position
Sensor (APPS) idle voltage. Failure to learn
this voltage may result in unnecessary diagnos-
tic trouble codes. Refer to ECM Removal/Instal-
lation for learning procedures.
The ECM receives input signals from various
switches and sensors. Based on these inputs, the
ECM regulates various engine and vehicle operations
through different system components. These compo-
nents are referred to asECM Outputs.The sensors
and switches that provide inputs to the ECM are
consideredECM Inputs.NOTE: ECM Inputs:
²Accelerator Pedal Position Sensor (APPS) Volts
²APPS1 Signal Ð For off engine APPS
²APPS2 Signal Ð For off engine APPS
²APPS Idle Validation Switches #1 and #2
²Battery voltage
²Camshaft Position Sensor (CMP)
²CCD bus (+) circuits
²CCD bus (-) circuits
²Crankshaft Position Sensor (CKP)
²Data link connection for DRB scan tool
²Engine Coolant Temperature (ECT) sensor
²Ground circuits
²Fuel Pressure Sensor
²Battery Temperature
²Fan speed
²Inlet Air Temperature Sensor/Pressure Sensor
²Intake Air Temperature Sensor/MAP Sensor
²Oil Pressure SWITCH
²Power ground
²Sensor return
²Signal ground
²Water-In-Fuel (WIF) sensor
NOTE: ECM Outputs:
After inputs are received by the ECM, certain sen-
sors, switches and components are controlled or reg-
ulated by the ECM. These are consideredECM
Outputs.These outputs are for:
²CCD bus (+) circuits
²CCD bus (-) circuits
²CKP and APPS outputs to the PCM
²Data link connection for DRB scan tool
²Five volt sensor supply
²Fuel transfer (lift) pump
²Intake manifold air heater relays #1 and #2 con-
trol circuits
²Malfunction indicator lamp (Check engine lamp)
(databus)
²Oil Pressure Swith/warning lamp (databus)
²Fuel Control Actuator
²Wait-to-start warning lamp (databus)
²Fan Clutch PWM
²Water-In-Fuel (WIF) warning lamp (databus)
REMOVAL
The Engine Control Module (ECM) is bolted to a
support bracket near the fuel filter. The support
bracket mounts to the block with four capscrews and
vibration isolators. A ground wire is fastened to the
bracket. The other end of the wire is fastened to the
engine block.
(1) Record any Diagnostic Trouble Codes (DTC's)
found in the ECM.
Fig. 2 DIESEL ECM
1 - ENGINE CONTROL MODULE (ECM)
2 - ECM MOUNTING BOLT
3 - 50-WAY CONNECTOR
4 - SUPPORT PLATE
5 - 60-WAY CONNECTOR
8E - 4 ELECTRONIC CONTROL MODULESDR

To avoid possible voltage spike damage to either
the Engine Control Module ECM, ignition key must
be off, and negative battery cables must be discon-
nected before unplugging ECM connectors.
(2) Disconnect both negative battery cables at both
batteries.
(3) Remove the 50±way and 60±way connector
bolts at the ECM. Note: Tthe connector bolt is a
female allen head. As bolt is being removed, very car-
fully remove connectors from the ECM.
(4) Remove five ECM mounting bolts and remove
ECM form the vehicle (Fig. 3).
INSTALLATION
Do not apply paint to ECM. Poor ground will
result.
(1) Position ECM to ECM support bracket and
install five mounting bolts. Tighten bolts to 24 N´m
(18 ft. lbs.).
(2) Check pin connectors in ECM and the 50±way
and 60±way connectors for corrosion or damage.
Repair as necessary.
(3) Clean pins in the 50±way and 60±way electri-
cal connectors with a quick-dry electrical contact
cleaner.
(4) Very carefully install the 50±way and 60±way
connectors to ECM. Tighten connector allen bolts.
(5) Install both negative battery cables.(6)Turn key to ON position. Without starting
engine, slowly press throttle pedal to floor and
then slowly release. This step must be done
(one time) to ensure accelerator pedal position
sensor calibration has been learned by ECM. If
not done, possible DTC's may be set.
(7) Use DRB scan tool to erase any stored compan-
ion DTC's from ECM.
FRONT CONTROL MODULE
DESCRIPTION
The Front Control Module (FCM) is a micro con-
troller based module located in the left front corner
of the engine compartment. On this model the inte-
grated power module must be positioned aside in
order to access the front control module. The front
control module mates to the power distribution cen-
ter to form the Integrated Power Module (IPM). The
integrated power module connects directly to the bat-
tery and provides the primary means of circuit pro-
tection and power distribution for all vehicle
electrical systems. The front control module controls
power to some of these vehicle systems electrical and
electromechanical loads based on inputs received
from hard wired switch inputs and data received on
the PCI bus circuit (J1850).
For information on theIntegrated Power Mod-
ule Refer to the Power Distribution Sectionof
the service manual.
OPERATION
As messages are sent over the PCI bus circuit, the
front control module reads these messages and con-
trols power to some of the vehicles electrical systems
by completing the circuit to ground (low side driver)
or completing the circuit to 12 volt power (high side
driver). The following functions areControlledby
the Front Control Module:
²Headlamp Power with Voltage Regulation
²Windshield Wiper ªON/OFFº Relay Actuation
²Windshield Wiper ªHI/LOº Relay Actuation
²Windshield Washer Pump Motor
²Fog Lamp Relay Actuation
²Park Lamp Relay Actuation
²Horn Relay Actuation
The following inputs areReceived/Monitoredby
the Front Control Module:
²B+ Connection Detection
²Power Ground
²Ambient Temperature Sensing
²Ignition Switch Run
²Washer Fluid Level Switch
²Windshield Wiper Park Switch
²PCI Bus Circuit
Fig. 3 DIESEL ECM
1 - ENGINE CONTROL MODULE (ECM)
2 - ECM MOUNTING BOLT
3 - 50-WAY CONNECTOR
4 - SUPPORT PLATE
5 - 60-WAY CONNECTOR
DRELECTRONIC CONTROL MODULES 8E - 5
ENGINE CONTROL MODULE (Continued)