with automatic transmission, place gearshift selector
lever in Park position.
(4) Verify that all lamps and accessories are
turned off.
(5) To prevent a gasoline engine from starting,
remove Automatic ShutDown (ASD) relay. To prevent
a diesel engine from starting, remove Fuel Pump
Relay. These relays are located in Power Distribution
Center (PDC). Refer to label on PDC cover for relay
location.
WARNING: IF EQUIPPED WITH DIESEL ENGINE,
ATTEMPT TO START ENGINE A FEW TIMES
BEFORE PROCEEDING WITH FOLLOWING STEP.
(6) Rotate and hold ignition switch in Start posi-
tion. Note cranking voltage and current (amperage)
draw readings shown on volt-ampere tester.
(a) If voltage reads below 9.6 volts, refer to
Starter Motorin Diagnosis and Testing. If starter
motor is OK, refer toEngine Diagnosisin 9,
Engine for further testing of engine. If starter
motor is not OK, replace faulty starter motor.
(b) If voltage reads above 9.6 volts and current
(amperage) draw reads below specifications, refer
toFeed Circuit Testin this section.
(c) If voltage reads 12.5 volts or greater and
starter motor does not turn, refer toControl Cir-
cuit Testingin this section.
(d) If voltage reads 12.5 volts or greater and
starter motor turns very slowly, refer toFeed Cir-
cuit Testin this section.
NOTE: A cold engine will increase starter current
(amperage) draw reading, and reduce battery volt-
age reading.FEED CIRCUIT TEST
The starter feed circuit test (voltage drop method)
will determine if there is excessive resistance in
high-amperage feed circuit. For complete starter wir-
ing circuit diagrams, refer 8, Wiring Diagrams.
When performing these tests, it is important to
remember that voltage drop is giving an indication of
resistance between two points at which voltmeter
probes are attached.
Example:When testing resistance of positive bat-
tery cable, touch voltmeter leads to positive battery
cable clamp and cable connector at starter solenoid.
If you probe positive battery terminal post and cable
connector at starter solenoid, you are reading com-
bined voltage drop in positive battery cable clamp-to-
terminal post connection and positive battery cable.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing tests,
be certain that following procedures are accom-
plished:
²Battery is fully-charged and load-tested. Refer to
Batteryin 8, Battery.
²Fully engage parking brake.
²If equipped with manual transmission, place
gearshift selector lever in Neutral position and block
clutch pedal in fully depressed position. If equipped
with automatic transmission, place gearshift selector
lever in Park position.
²Verify that all lamps and accessories are turned
off.
²To prevent a gasoline engine from starting,
remove Automatic ShutDown (ASD) relay. To prevent
a diesel engine from starting, remove Fuel Pump
Relay. These relays are located in Power Distribution
Center (PDC). Refer to label on PDC cover for relay
location.
(1) Connect positive lead of voltmeter to negative
battery cable terminal post. Connect negative lead of
voltmeter to negative battery cable clamp (Fig. 2).
Rotate and hold ignition switch in Start position.
Observe voltmeter. If voltage is detected, correct poor
contact between cable clamp and terminal post.
Note: Certain diesel equipped models use dual
batteries. If equipped with dual battery system,
procedure must be performed twice, once for
each battery.
(2) Connect positive lead of voltmeter to positive
battery terminal post. Connect negative lead of volt-
meter to battery positive cable clamp (Fig. 3). Rotate
and hold ignition switch in Start position. Observe
voltmeter. If voltage is detected, correct poor contact
between cable clamp and terminal post.Note: Cer-
tain diesel equipped models use dual batteries.
If equipped with dual battery system, this pro-
cedure must be performed twice, once for each
battery.
Fig. 1 VOLTS-AMPS TESTER CONNECTIONS -
TYPICAL
1 - POSITIVE CLAMP
2 - NEGATIVE CLAMP
3 - INDUCTION AMMETER CLAMP
DRSTARTING 8F - 31
STARTING (Continued)
(3) Connect voltmeter to measure between battery
positive terminal post and starter solenoid battery
terminal stud (Fig. 4). Rotate and hold ignition
switch in Start position. Observe voltmeter. If read-
ing is above 0.2 volt, clean and tighten battery cable
connection at solenoid. Repeat test. If reading is still
above 0.2 volt, replace faulty positive battery cable.
Note: Certain diesel equipped models use dual
batteries. If equipped with dual battery system,
this procedure must be performed on driver
side battery only.
(4) Connect voltmeter to measure between nega-
tive battery terminal post and a good clean ground
on engine block (Fig. 5). Rotate and hold ignition
switch in Start position. Observe voltmeter. If read-
ing is above 0.2 volt, clean and tighten negative bat-tery cable attachment on engine block. Repeat test. If
reading is still above 0.2 volt, replace faulty negative
battery cable.Note: Certain diesel equipped mod-
els use dual batteries. If equipped with dual
battery system, this procedure must be per-
formed twice, once for each battery.
(5) Connect positive lead of voltmeter to starter
housing. Connect negative lead of voltmeter to nega-
tive battery terminal post (Fig. 6). Rotate and hold
ignition switch in Start position. Observe voltmeter.
If reading is above 0.2 volt, correct poor starter to
engine block ground contact.Note: Certain diesel
equipped models use dual batteries. If equipped
with dual battery system, this procedure must
be performed on driver side battery only.
Fig. 2 TEST BATTERY NEGATIVE CONNECTION
RESISTANCE - TYPICAL
1 - VOLTMETER
2 - BATTERY
Fig. 3 TEST BATTERY POSITIVE CONNECTION
RESISTANCE - TYPICAL
1 - VOLTMETER
2 - BATTERY
Fig. 4 TEST BATTERY POSITIVE CABLE
RESISTANCE - TYPICAL
1 - BATTERY
2 - VOLTMETER
3 - STARTER MOTOR
Fig. 5 TEST GROUND CIRCUIT RESISTANCE -
TYPICAL
1 - VOLTMETER
2 - BATTERY
3 - ENGINE GROUND
8F - 32 STARTINGDR
STARTING (Continued)
(6) If equipped with dual battery system (certain
diesel equipped models), connect positive lead of volt-
meter to positive battery cable clamp on battery
located on left side of vehicle. Connect negative lead
of voltmeter to positive battery terminal post on bat-
tery located on right side of vehicle. Rotate and hold
ignition switch in Start position. Observe voltmeter.If reading is above 0.2 volt, clean and tighten battery
cables at both batteries. Repeat test. If reading is
still above 0.2 volt, replace faulty positive battery
cable.
If resistance tests detect no feed circuit problems,
refer toStarter Motorin the Diagnosis and Testing.
CONTROL CIRCUIT TESTING
The starter control circuit components should be
tested in the order in which they are listed, as fol-
lows:
²Starter Relay- Refer toStarter RelayDiag-
nosis and Testing.
²Starter Solenoid- Refer toStarter Motor
Diagnosis and Testing.
²Ignition Switch- Refer toIgnition Switch
and Key Lock Cylinder
²Clutch Pedal Position Switch- If equipped
with manual transmission, refer toClutch Pedal
Position Switchin 6, Clutch.
²Park/Neutral Position Switch- If equipped
with automatic transmission, refer toPark/Neutral
Position Switchin 21, Transmission.
²Wire harnesses and connections- Refer to 8,
Wiring Diagrams.
SPECIFICATIONS
STARTING SYSTEM
Starter Motor and Solenoid
Manufacturer Denso Denso Denso
Part Number 56028715AD 56027703AD 4741012
Engine Application 3.7L / 4.7L / 5.7L / 5.9L 8.0L 5.9L Diesel
Power Rating1.4 Kilowatt / 1.9
Horsepower1.4 Kilowatt / 1.9
Horsepower2.7 Kilowatt / 3.6
Horsepower
Voltage 12 Volts 12 Volts 12 Volts
Number of Brushes 4 4 4
Drive Type Gear Reduction Gear Reduction Conventional
Free Running Test Voltage 11 Volts 11 Volts 11 Volts
Free Running Test Amperage
Draw73 Amperes 73 Amperes 200 Amperes
Free Running Test Minimum
Speed3601 rpm 3601 rpm 3000
Solenoid Closing Maximum
Voltage Required7.5 Volts 7.5 Volts 8.0 Volts
* Cranking Amperage Draw
Test125 - 250 Amperes 125 - 250 Amperes 450 - 700 Amperes
* Test at operating temperature. Cold engine, tight (new) engine, or heavy oil will increase starter amperage draw.
Fig. 6 TEST STARTER GROUND - TYPICAL
1 - STARTER MOTOR
2 - BATTERY
3 - VOLTMETER
DRSTARTING 8F - 33
STARTING (Continued)
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)
(4) Move starter motor towards front of vehicle far
enough for nose of starter pinion housing to clear
housing. Always support starter motor during this
process. Do not let starter motor hang from wire har-
ness.
(5) Tilt nose downwards and lower starter motor
far enough to access and remove nuts securing
starter wiring harness to starter (Fig. 13). Do not let
starter motor hang from wire harness.
(6) Remove starter motor from engine. Note: Cer-
tain diesel engines use an aluminum spacer (Fig. 12).
Note position and orientation of spacer before
removal.
5.9L Gas
(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.
(4) Remove nut and lock washer securing starter
motor to mounting stud (Fig. 14).
(5) While supporting starter motor, remove upper
mounting bolt from starter motor.
(6) If equipped with automatic transmission, slide
cooler tube bracket forward on tubes far enough for
starter motor mounting flange to be removed from
lower mounting stud.
(7) Move starter motor towards front of vehicle far
enough for nose of starter pinion housing to clear
Fig. 11 STARTER R/I - 5.7L
1 - STARTER MOTOR
2 - MOUNTING BOLTS
Fig. 12 STARTER R/I - 5.9L DIESEL
1 - MOUNTING BOLTS (3)
2 - STARTER MOTOR
3 - SPACER (CERTAIN TRANSMISSIONS)
Fig. 13 STARTER ELECTRICAL CONNECTORS -
5.9L DIESEL
1 - STARTER MOTOR
2 - BATTERY CABLE NUT
3 - SOLENOID NUT
4 - HARNESS ASSEMBLY
8F - 36 STARTINGDR
STARTER MOTOR (Continued)
housing. Always support starter motor during this
process, do not let starter motor hang from wire har-
ness.
(8) Tilt nose downwards and lower starter motor
far enough to access and remove nut that secures
battery positive cable wire harness connector eyelet
to solenoid battery terminal stud. Do not let starter
motor hang from wire harness.
(9) Remove battery positive cable wire harness
connector eyelet from solenoid battery terminal stud.
(10) Disconnect battery positive cable wire harness
connector from solenoid terminal connector recepta-
cle.
(11) Remove starter motor.
INSTALLATION
3.7L / 4.7L
(1) Connect solenoid wire to starter motor (snaps
on).
(2) Position battery cable to solenoid stud. Install
and tighten battery cable eyelet nut. Refer to Torque
Specifications. Do not allow starter motor to hang
from wire harness.
(3) Position starter motor to transmission.
(4) If equipped with automatic transmission, slide
cooler tube bracket into position.(5) Install and tighten both bolts (auto. trans.), or
1 nut and 1 bolt (man. trans.). Refer to Torque Spec-
ifications.
(6) Lower vehicle.
(7) Connect negative battery cable.
5.7L
(1) Connect solenoid wire to starter motor (snaps
on).
(2) Position battery cable to solenoid stud. Install
and tighten battery cable eyelet nut. Refer to Torque
Specifications. Do not allow starter motor to hang
from wire harness.
(3) Position starter motor to engine.
(4) If equipped with automatic transmission, slide
cooler tube bracket into position.
(5) Install and tighten both mounting bolts. Refer
to Torque Specifications.
(6) Lower vehicle.
(7) Connect negative battery cable.
5.9L Diesel
(1)If Equipped:Position and hold aluminum
spacer to rear of starter while positioning starter to
engine.
(2) Connect solenoid wire to starter motor. Tighten
nut.
(3) Position battery cable to starter stud. Install
and tighten battery cable nut. Refer to Torque Spec-
ifications. Do not allow starter motor to hang from
wire harness.
(4) Position starter motor to transmission.
(5) If equipped with automatic transmission, slide
cooler tube bracket into position.
(6) Install and tighten 3 starter mounting bolts.
Refer to Torque Specifications.
(7) Lower vehicle.
(8) Connect both negative battery cables to both
batteries.
5.9L Gas
(1) Connect solenoid wire to starter motor (snaps
on).
(2) Position battery cable to solenoid stud. Install
and tighten battery cable eyelet nut. Refer to Torque
Specifications. Do not allow starter motor to hang
from wire harness.
(3) Position starter motor to transmission.
(4) If equipped with automatic transmission, slide
cooler tube bracket into position.
(5) Install and tighten both bolts (auto. trans.), or
1 nut and 1 bolt (man. trans.). Refer to Torque Spec-
ifications.
(6) Lower vehicle.
(7) Connect negative battery cable.
Fig. 14 STARTER R/I - 5.9L GAS
1 - ENGINE
2 - STARTER MOUNTING FLANGE
3 - STUD
4 - STARTER MOTOR
5 - LOCK WASHER
6 - NUT
7 - BRACKET
8 - BOLT
9 - POSITIVE BATTERY CABLE WIRE HARNESS
10 - POSITIVE BATTERY CABLE WIRE HARNESS NUT
DRSTARTING 8F - 37
STARTER MOTOR (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
OPERATION
The heated seat module receives fused battery cur-
rent through the Integrated Power Module only when
the engine is running. The heated seat switches
receive battery current through fuse #48 in the Inte-
grated Power Module only when the ignition switch
is in the On position. The heated seat module shares
a common ground circuit with each of the heated seat
elements. The heated seat system will only operate
when the surface temperature of the seat cushion is
below the designed temperature set points of the sys-
tem.
The heated seat system will also automatically
turn off whenever the ignition switch is turned to
any position except On, or if the engine quits run-
ning. If the ignition switch is turned to the Off posi-
tion or if the engine quits running while a heated
seat is ON, the heated seat will remain Off after the
engine is restarted until a heated seat switch is
depressed again. This helps prevent the vehicles bat-
tery from being drained by the heated seat system.The heated seat module monitors inputs from the
heated seat sensors and the heated seat switches. In
response to these inputs the heated seat module uses
its internal programming to control 12v to the heated
seat elements in both front seats and to control the
heated seat LED indicator lamps located in both of
the heated seat switches. The heated seat module is
also programmed to provide self-diagnostics, if a
problem with the heated seat system is detected. If
the module detects certain failures within the heated
seat system, it will provide a visual indication of the
failure by flashing the indicator lamps in the appro-
priate heated seat switch. The heated seat module
will automatically turn off the heated seat elements
if it detects a short or open in the heated seat ele-
ment circuit or a heated seat sensor value that is out
of range.
DIAGNOSIS AND TESTING - HEATED SEAT
SYSTEM
HEATED SEAT SYSTEM SELF-DIAGNOSIS
The heated seat system is capable of performing
some self-diagnostics. The following table depicts the
various monitored failures which will be reported to
the vehicle operator or technician by flashing the
individual heated seat switch Light Emitting Diode
(LED) indicator lamps. Refer to the HEATED SEAT
SYSTEM SELF-DIAGNOSIS table for failure identi-
fication. The drivers heated seat switch indicator
lamps will flash if a failure occurs in the driver
heated seat, and the passengers heated seat switch
indicator lamps will flash for a passenger heated seat
failure. If a monitored heated seat system failure
occurs, the switch indicator lamps will flash at a
pulse rate of about one-half second on, followed by
about one-half second off for a duration of about one
minute after the switch for the faulty heated seat is
depressed in either the Low or High direction. This
process will repeat every time the faulty heated seat
switch is actuated until the problem has been cor-
rected.
HEATED SEAT SYSTEM SELF-DIAGNOSIS
Monitored FailureSwitch High
Indicator LampSwitch Low
Indicator Lamp
Heated Seat
Element ShortedFlashing Flashing
Heated Seat
Element OpenFlashing Off
Heated Seat
Sensor Value Out
of RangeOff Flashing
Fig. 1 DR Heated Seat System Diagram
1 - WIRE HARNESS
2 - DRIVER HEATED SEAT SWITCH
3 - PASSENGER HEATED SEAT SWITCH
4 - PASSENGER HEATED SEAT CUSHION ELEMENT
5 - SEAT CUSHION/BACK ELEMENT ELECTRICAL CONNECTOR
LOCATION
6 - DRIVER HEATED SEAT BACK ELEMENT
7 - DRIVER HEATED SEAT CUSHION ELEMENT
8 - HEATED SEAT MODULE
8G - 4 HEATED SEAT SYSTEMDR
HEATED SEAT SYSTEM (Continued)