check oil DODGE RAM 2003 Service Owner's Manual

(6) Remove the power steering cooler mounting
bolts and position the power steering cooler out of
the way.
(7) Disconnect the transmission cooler lines at the
transmission. The transmission cooler will remain on
the radiator and can be removed as an assembly.
(8) Remove the lower shroud assembly and the
electronic viscous fan wiring from the upper shroud
assembly.
(9) Remove the two radiator upper mounting bolts
(Fig. 36).
(10) Lift radiator straight up and out of engine
compartment. The bottom of the radiator is equipped
with two alignment dowels that fit into holes in the
lower radiator support panel. Rubber biscuits (insu-
lators) are installed to these dowels. Take care not to
damage cooling fins or tubes on the radiator and air
conditioning condenser when removing.
CLEANING
Clean radiator fins are necessary for good heat
transfer. The radiator and oil cooler fins should be
cleaned when an accumulation of debris has
occurred. With the engine cold, apply cold water and
compressed air to the back (engine side) of the radi-
ator to flush the radiator and/or oil coolers of debris.
INSPECTION
Inspect the radiator side tanks for cracks, broken
or missing fittings also inspect the joint where the
tanks seam up to the radiator core for signs of leak-
age and/or deteriorating seals.
Inspect radiator core for corroded, bent or missing
cooling fins. Inspect the core for bent or damaged
cooling tubes.
INSTALLATION
(1) Install rubber insulators to alignment dowels
at lower part of radiator.
(2) Lower the radiator into position while guiding
the two alignment dowels into lower radiator sup-
port. Different alignment holes are provided in the
lower radiator support for each engine application.
(3) Install two upper radiator mounting bolts.
Tighten bolts to 11 N´m (95 in. lbs.) torque.
(4) Connect both radiator hoses and install hose
clamps.
(5) Connect transmission cooler lines to radiator
tank. Inspect quick connect fittings for debris and
install until an audible ªclickº is heard. Pull apart to
verify connection.
(6) Position power steering cooler on the radiator
and tighten nuts to 8.5M´N (75 in. lbs.)
(7) Attach electronic viscous fan wiring to upper
shroud ands install lower shroud.
(8) Position coolant recover tank hose, washer bot-
tle hose and the positive battery cable into the clips
located on the top of the radiator.
(9) Install air box and turbocharger inlet hose.
Tighten clamps to 4 N´M (35 in. lbs.).
(10) Position heater controls tofull heatposition.
(11) Fill cooling system with coolant (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(12) Operate engine until it reaches normal tem-
perature. Check cooling system and automatic trans-
mission (if equipped) fluid levels.
RADIATOR PRESSURE CAP
DESCRIPTION
All cooling systems are equipped with a pressure
cap (Fig. 37). For 5.9L engines, the pressure cap is
located on top of the radiator outlet tank. For the
3.7L/4.7L engines, the pressure cap is located on top
of the coolant degas container. The cap releases pres-
sure at some point within a range of 97-to-124 kPa
(14-to-18 psi). The pressure relief point (in pounds) is
engraved on top of the cap
The cooling system will operate at pressures
slightly above atmospheric pressure. This results in a
higher coolant boiling point allowing increased radi-
ator cooling capacity. The cap contains a spring-
Fig. 36 Fan Shroud MountingÐ5.9L Diesel Engine
1 - RADIATOR SUPPORT
2 - UPPER FAN SHROUD
3 - BOLTS (2)
4 - LOWER FAN SHROUD
5 - RADIATOR
7 - 60 ENGINEDR
RADIATOR - 5.9L DIESEL (Continued)

INSPECTION
Visually inspect the water pump and replace if it
has any of the following conditions:
²The body is cracked or damaged
²Water leaks from the shaft seal. This is evident
by traces of coolant below the vent hole
²Loose or rough turning bearing.
²Impeller rubbing the pump body
INSTALLATION
(1) Install new O-ring seal in groove on water
pump (Fig. 51).
(2) Install water pump. Tighten mounting bolts to
24 N´m (18 ft. lbs.) torque.
(3) Install accessory drive belt. Refer to procedure
in this group.
(4) Install the bolt retaining the wiring harness
near top of water pump.
(5) Fill cooling system. Refer to Refilling Cooling
System in this section.
(6) Connect both battery cables.
(7) Start and warm the engine. Check for leaks.
WATER PUMP INLET TUBE -
5.9L
REMOVAL
REMOVAL - WATER PUMP BYPASS HOSE
WITH AIR CONDITIONING
If equipped with A/C, the generator and A/C com-
pressor along with their common mounting bracket
(Fig. 52) must be partially removed. Removing thegenerator or A/C compressor from their mounting
bracket is not necessary. Also, discharging the A/C
system is not necessary.Do notremove any refriger-
ant lines from A/C compressor.
WARNING: THE A/C SYSTEM IS UNDER PRESSURE
EVEN WITH THE ENGINE OFF. REFER TO REFRIG-
ERANT WARNINGS IN SECTION 24 - HEATING AND
AIR CONDITIONING.
(1) Disconnect the negative battery cable.
(2) 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.
(3) Remove the upper radiator hose clamp at the
radiator. A special clamp tool must be used to remove
the constant tension clamps. Removethe hose at the
radiator.
(4) Unplug the wiring harness from the A/C com-
pressor.
(5) Remove the air cleaner assembly.
(6) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(7) The drive belt idler pulley must be removed to
gain access to one of the A/C compressor/generator
bracket mounting bolts. Remove the idler pulley bolt
and remove idler pulley (Fig. 53).
(8) Remove the engine oil dipstick tube mounting
bolt at the side of the A/C-generator mounting
bracket.
(9) Disconnect the throttle body control cables.
Fig. 51 Pump O-ring Seal
1 - O-RING SEAL
2 - GROOVE
3 - WATER PUMP
Fig. 52 Generator - A/C Compressor Mounting
Bracket - Typical
7 - 68 ENGINEDR
WATER PUMP - 5.9L DIESEL (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)

(5) Remove the bolts attaching the transmission
cooler to the radiator.
(6) Remove oil cooler from the vehicle. Take care
not to damage the radiator core or transmission
cooler tubes.
DISASSEMBLY - 5.9L ONLY
NOTE: The transmission oil cooler uses an internal
thermostat to control transmission oil flow through
the cooler. This thermostat is servicable.
(1) Remove the transmission oil cooler (Refer to 7 -
COOLING/TRANSMISSION/TRANS COOLER -
REMOVAL).
(2) Remove the snap ring retaining the thermostat
end plug (Fig. 3).
(3) Remove the end plug, thermostat and spring
from transmission oil cooler (Fig. 3).
ASSEMBLY - 5.9L ONLY
(1) Throughly clean the thermostat bore on the
transmission oil cooler.
(2) Install the new spring, thermostat, end plug
and snap ring.(3) Install the transmission oil cooler (Refer to 7 -
COOLING/TRANSMISSION/TRANS COOLER -
INSTALLATION).
INSTALLATION
(1) Position the transmission cooler tubes to the
front of the radiator.
(2) Snap the transmission cooler tubes into the
clips on the side of the radiator tank.
(3) Install the transmission cooler attaching bolts.
Tighten the bolts to 16 N´m (140 in. lbs.).
(4) inspect the quick connect fittings for debris and
install the quick connect fitting on the cooler tube
until an audible ªclickº is heard. Pull apart the con-
nection to verify proper installation and install the
secondary latches.
(5) Connect the battery negative cable.
(6) Start the engine and check all fittings for
leaks.
(7) Check the fluid level in the automatic trans-
mission. Refer to the appropriate transmission sec-
tion(Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 45RFE/545RFE/FLUID - STANDARD
PROCEDURE) or(Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 46RE/FLUID - STAN-
DARD PROCEDURE).
TRANS COOLER - 5.9L DIESEL
DESCRIPTION
All diesel models equipped with an automatic
transmission are equipped with both a main water-
to-oil cooler and a separate air-to-oil cooler. Both cool-
Fig. 2 Cooling Module - 3.7L/4.7L/5.7L
1 - TRANS OIL COOLER
2 - TRANS OIL COOLER MOUNTING BOLT (3)
3 - POWER STEERING OIL COOLER
4 - POWER STEERING OIL COOLER MOUNTING BOLT
5 - TRANS OIL COOLER OUTLET
6 - TRANS OIL COOLER INLET
7 - COOLER LINE CLIP
8 - COOLER LINE CLIP
9 - RADIATOR
Fig. 3 Transmission Oil Cooler Thermostat
Removal/Installation
1 - THERMOSTAT HOUSING
2 - SPRING
3 - END PLUG
4 - SNAP RING
5 - THERMOSTAT
DRTRANSMISSION 7 - 73
TRANS COOLER (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)

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

OPERATION
OPERATION - PCM
The PCM operates the fuel system. The PCM is a
pre-programmed, triple microprocessor digital com-
puter. It regulates ignition timing, air-fuel ratio,
emission control devices, charging system, certain
transmission features, speed control, air conditioning
compressor clutch engagement and idle speed. The
PCM can adapt its programming to meet changing
operating conditions.
The PCM receives input signals from various
switches and sensors. Based on these inputs, the
PCM regulates various engine and vehicle operations
through different system components. These compo-
nents are referred to as Powertrain Control Module
(PCM) Outputs. The sensors and switches that pro-
vide inputs to the PCM are considered Powertrain
Control Module (PCM) Inputs.
The PCM adjusts ignition timing based upon
inputs it receives from sensors that react to: engine
rpm, manifold absolute pressure, engine coolant tem-
perature, throttle position, transmission gear selec-
tion (automatic transmission), vehicle speed, power
steering pump pressure, and the brake switch.
The PCM adjusts idle speed based on inputs it
receives from sensors that react to: throttle position,
vehicle speed, transmission gear selection, engine
coolant temperature and from inputs it receives from
the air conditioning clutch switch and brake switch.
Based on inputs that it receives, the PCM adjusts
ignition coil dwell. The PCM also adjusts the gener-
ator charge rate through control of the generator
field and provides speed control operation.
NOTE: PCM Inputs:
²ABS module (if equipped)
²A/C request (if equipped with factory A/C)
²A/C select (if equipped with factory A/C)
²A/C pressure transducer
²Auto shutdown (ASD) sense
²Battery temperature sensor
²Battery voltage
²Brake switch
²J1850 bus (+) circuits
²J1850 bus (-) circuits
²Camshaft position sensor signal
²Crankshaft position sensor
²Data link connection for DRB scan tool
²EATX module (if equipped)
²Engine coolant temperature sensor
²Fuel level (through J1850 circuitry)
²Generator (battery voltage) output
²Ignition circuit sense (ignition switch in on/off/
crank/run position)²Intake manifold air temperature sensor
²Knock sensors (2 on 3.7L engine)
²Leak detection pump (switch) sense (if equipped)
²Manifold absolute pressure (MAP) sensor
²Oil pressure
²Oxygen sensors
²Park/neutral switch (auto. trans. only)
²Power ground
²Power steering pressure switch (if equipped)
²Sensor return
²Signal ground
²Speed control multiplexed single wire input
²Throttle position sensor
²Transfer case switch (4WD range position)
²Vehicle speed signal
NOTE: PCM Outputs:
²A/C clutch relay
²Auto shutdown (ASD) relay
²J1850 bus (+/-) circuits for: speedometer, voltme-
ter, fuel gauge, oil pressure gauge/lamp, engine temp.
gauge and speed control warn. lamp
²Data link connection for DRB scan tool
²EGR valve control solenoid (if equipped)
²EVAP canister purge solenoid
²Five volt sensor supply (primary)
²Five volt sensor supply (secondary)
²Fuel injectors
²Fuel pump relay
²Generator field driver (-)
²Generator field driver (+)
²Idle air control (IAC) motor
²Ignition coil(s)
²Leak detection pump (if equipped)
²Malfunction indicator lamp (Check engine lamp).
Driven through J1850 circuits.
²Oxygen sensor heater relays
²Oxygen sensors (pulse width modulated)
²Radiator cooling fan relay (pulse width modu-
lated)
²Speed control vacuum solenoid
²Speed control vent solenoid
²Tachometer (if equipped). Driven through J1850
circuits.
²Transmission convertor clutch circuit. Driven
through J1850 circuits.
OPERATION - 5 VOLT SUPPLIES
Primary 5±volt supply:
²supplies the required 5 volt power source to the
Crankshaft Position (CKP) sensor.
²supplies the required 5 volt power source to the
Camshaft Position (CMP) sensor.
²supplies a reference voltage for the Manifold
Absolute Pressure (MAP) sensor.
DRELECTRONIC CONTROL MODULES 8E - 11
POWERTRAIN CONTROL MODULE (Continued)

CHARGING
TABLE OF CONTENTS
page page
CHARGING
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - CHARGING
SYSTEM............................19
SPECIFICATIONS
GENERATOR RATINGS.................20
SPECIFICATIONS - TORQUE - GENERATOR
/ CHARGING SYSTEM..................20
BATTERY TEMPERATURE SENSOR
DESCRIPTION.........................21OPERATION...........................21
REMOVAL.............................21
INSTALLATION.........................21
GENERATOR
DESCRIPTION.........................22
OPERATION...........................22
REMOVAL.............................22
INSTALLATION.........................25
VOLTAGE REGULATOR
DESCRIPTION.........................27
OPERATION...........................27
CHARGING
DESCRIPTION
The charging system consists of:
²Generator
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM). Elec-
tronic Control Module (ECM) for diesel engines.
²Ignition switch
²Battery (refer to 8, Battery for information)
²Battery temperature sensor
²Check Gauges Lamp (if equipped)
²Voltmeter (refer to 8, Instrument Panel and
Gauges for information)
²Wiring harness and connections (refer to 8, Wir-
ing Diagrams for information)
OPERATION
The charging system is turned on and off with the
ignition switch. The system is on when the engine is
running and the ASD relay is energized. When the
ASD relay is on, voltage is supplied to the ASD relay
sense circuit at the PCM (ECM Diesel). This voltage
is connected through the PCM (ECM Diesel) and sup-
plied to one of the generator field terminals (Gen.
Source +) at the back of the generator.
The amount of direct current produced by the gen-
erator is controlled by the EVR (field control) cir-
cuitry contained within the PCM (ECM Diesel). This
circuitry is connected in series with the second rotor
field terminal and ground.
A battery temperature sensor, located in the bat-
tery tray housing, is used to sense battery tempera-
ture. This temperature data, along with data from
monitored line voltage, is used by the PCM (ECM
Diesel) to vary the battery charging rate. This isdone by cycling the ground path to control the
strength of the rotor magnetic field. The PCM then
compensates and regulates generator current output
accordingly.
All vehicles are equipped with On-Board Diagnos-
tics (OBD). All OBD-sensed systems, including EVR
(field control) circuitry, are monitored by the PCM
(ECM Diesel). Each monitored circuit is assigned a
Diagnostic Trouble Code (DTC). The PCM will store a
DTC in electronic memory for certain failures it
detects.
The Check Gauges Lamp (if equipped) monitors:
charging system voltage,engine coolant tempera-
ture and engine oil pressure. If an extreme condition
is indicated, the lamp will be illuminated. This is
done as reminder to check the three gauges. The sig-
nal to activate the lamp is sent via the CCD bus cir-
cuits. The lamp is located on the instrument panel.
Refer to 8, Instrument Panel and Gauges for addi-
tional information.
DIAGNOSIS AND TESTING - CHARGING
SYSTEM
The following procedures may be used to diagnose
the charging system if:
²the check gauges lamp (if equipped) is illumi-
nated with the engine running
²the voltmeter (if equipped) does not register
properly
²an undercharged or overcharged battery condi-
tion occurs.
Remember that an undercharged battery is often
caused by:
²accessories being left on with the engine not
running
DRCHARGING 8F - 19

SPECIFICATIONS - TORQUE - STARTING
SYSTEM
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Battery Cable Eyelet Nut at
Solenoid (large nut - gas engines)25 19 221
Battery Cable Eyelet Nut at
Solenoid (large nut - diesel engine)14 - 120
Starter Solenoid Nut (small nut -
diesel engine)6-55
Starter Mounting Bolts - Gas
Engines68 50 -
Starter Mounting Nut - Gas Engines 68 50 -
Starter Mounting Bolts - Diesel 43 32 -
STARTER MOTOR
DIAGNOSIS AND TESTING - STARTER MOTOR
Correct starter motor operation can be confirmed
by performing the following free running bench test.
This test can only be performed with starter motor
removed from vehicle. Refer to Specifications for
starter motor specifications.
(1) Remove starter motor from vehicle. Refer to
Starter Motor Removal and Installation.
(2) Mount starter motor securely in a soft-jawed
bench vise. The vise jaws should be clamped on the
mounting flange of starter motor. Never clamp on
starter motor by field frame.
(3) Connect a suitable volt-ampere tester and a
12-volt battery to starter motor in series, and set
ammeter to 100 ampere scale. See instructions pro-
vided by manufacturer of volt-ampere tester being
used.
(4) Install jumper wire from solenoid terminal to
solenoid battery terminal. The starter motor should
operate. If starter motor fails to operate, replace
faulty starter motor assembly.
(5) Adjust carbon pile load of tester to obtain free
running test voltage. Refer to Specifications for
starter motor free running test voltage specifications.
(6) Note reading on ammeter and compare reading
to free running test maximum amperage draw. Refer
to Specifications for starter motor free running test
maximum amperage draw specifications.
(7) If ammeter reading exceeds maximum amper-
age draw specification, replace faulty starter motor
assembly.
STARTER SOLENOID
This test can only be performed with starter motor
removed from vehicle.(1) Remove starter motor from vehicle. Refer to
Starter Motor Removal and Installation.
(2) Disconnect wire from solenoid field coil termi-
nal.
(3) Check for continuity between solenoid terminal
and solenoid field coil terminal with a continuity
tester (Fig. 7). There should be continuity. If OK, go
to Step 4. If not OK, replace faulty starter motor
assembly.
(4) Check for continuity between solenoid terminal
and solenoid case (Fig. 8). There should be continuity.
If not OK, replace faulty starter motor assembly.
REMOVAL
3.7L / 4.7L
(1) Disconnect and isolate negative battery cable.
(2) Raise and support vehicle.
(3) Note: If equipped with 4WD and certain trans-
missions, a support bracket is used between front
axle and side of transmission. Remove 2 support
bracket bolts at transmission. Pry support bracket
slightly to gain access to lower starter mounting bolt.
Fig. 7 CONTINUITY BETWEEN SOLENOID AND
FIELD COIL TERMINALS - TYPICAL
1 - OHMMETER
2 - SOLENOID TERMINAL
3 - FIELD COIL TERMINAL
8F - 34 STARTINGDR
STARTING (Continued)

STARTER MOTOR RELAY
DESCRIPTION
The starter relay is an electromechanical device
that switches battery current to the pull-in coil of the
starter solenoid when ignition switch is turned to
Start position. The starter relay is located in the
Power Distribution Center (PDC) in the engine com-
partment. See PDC cover for relay identification and
location.
The starter relay is a International Standards
Organization (ISO) relay. Relays conforming to ISO
specifications have common physical dimensions, cur-
rent capacities, terminal patterns, and terminal func-
tions.
The starter relay cannot be repaired or adjusted. If
faulty or damaged, it must be replaced.
OPERATION
The ISO relay consists of an electromagnetic coil, a
resistor or diode, and three (two fixed and one mov-
able) electrical contacts. The movable (common feed)
relay contact is held against one of the fixed contacts
(normally closed) by spring pressure. When electro-
magnetic coil is energized, it draws the movable con-
tact away from normally closed fixed contact, and
holds it against the other (normally open) fixed con-
tact.
When electromagnetic coil is de-energized, spring
pressure returns movable contact to normally closed
position. The resistor or diode is connected in parallel
with electromagnetic coil within relay, and helps to
dissipate voltage spikes produced when coil is de-en-
ergized.
DIAGNOSIS AND TESTING - STARTER RELAY
The starter relay (Fig. 15) is located in Power Dis-
tribution Center (PDC). Refer to PDC cover for relay
identification and location. For complete starter relay
wiring circuit diagrams, refer to 8, Wiring Diagrams.
(1) Remove starter relay from PDC.
(2) A relay in de-energized position should have
continuity between terminals 87A and 30, and no
continuity between terminals 87 and 30. If OK, go to
Step 3. If not OK, replace faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   5 ohms. If OK, go to Step
4. If not OK, replace faulty relay.
(4) Connect 12V battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, perform Relay Circuit Test that fol-
lows. If not OK, replace faulty relay.RELAY CIRCUIT TEST
(1) The relay common feed terminal cavity (30) is
connected to battery voltage and should be hot at all
times. If OK, go to Step 2. If not OK, repair open cir-
cuit to fuse in PDC as required.
(2) The relay normally closed terminal (87A) is
connected to terminal 30 in the de-energized position,
but is not used for this application. Go to Step 3.
(3) The relay normally open terminal (87) is con-
nected to common feed terminal (30) in the energized
position. This terminal supplies battery voltage to
starter solenoid field coils. There should be continu-
ity between cavity for relay terminal 87 and starter
solenoid terminal at all times. If OK, go to Step 4. If
not OK, repair open circuit to starter solenoid as
required.
(4) The coil battery terminal (86) is connected to
electromagnet in relay. It is energized when ignition
switch is held in Start position. On vehicles with
manual transmission, clutch pedal must be fully
depressed for this test. Check for battery voltage at
cavity for relay terminal 86 with ignition switch in
Start position, and no voltage when ignition switch is
released to On position. If OK, go to Step 5. If not
OK with automatic transmission, check for open or
short circuit to ignition switch and repair, if required.
If circuit to ignition switch is OK, refer toIgnition
Switch and Key Lock Cylinder. If not OK with a
manual transmission, check circuit between relay
and clutch pedal position switch for open or a short.
If circuit is OK, refer toClutch Pedal Position
Switchin 6 , Clutch.
Fig. 15 TYPE 1 RELAY
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
8F - 38 STARTINGDR