(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.
(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
Part Number 56028715AD 4741012
Engine Application 3.7L / 4.7L / 5.7L 5.9L Diesel
Power Rating1.4 Kilowatt / 1.9
Horsepower2.7 Kilowatt / 3.6
Horsepower
Fig. 5 TEST GROUND CIRCUIT RESISTANCE -
TYPICAL
1 - VOLTMETER
2 - BATTERY
3 - ENGINE GROUND
Fig. 6 TEST STARTER GROUND - TYPICAL
1 - STARTER MOTOR
2 - BATTERY
3 - VOLTMETER
DRSTARTING 8F - 31
STARTING (Continued)
(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.
(4) Remove 1 bolt and 1 nut if equipped with a
manual transmission (Fig. 9).
(5) Remove 2 bolts if equipped with an automatic
transmission (Fig. 10).
(6) 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.
(7) 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.
(8) Remove battery positive cable wire harness
connector eyelet from solenoid battery terminal stud.
(9) Disconnect battery positive cable wire harness
connector from solenoid terminal connector recepta-
cle.
(10) Remove starter motor.
Fig. 7 CONTINUITY BETWEEN SOLENOID AND
FIELD COIL TERMINALS - TYPICAL
1 - OHMMETER
2 - SOLENOID TERMINAL
3 - FIELD COIL TERMINAL
Fig. 8 CONTINUITY BETWEEN SOLENOID
TERMINAL AND CASE - TYPICAL
1 - SOLENOID TERMINAL
2 - OHMMETER
3 - SOLENOID
Fig. 9 STARTER R/I - 3.7L/4.7L - MAN. TRANS.
1 - EYELET TERMINAL
2 - NUT
3 - BRACKET
4 - STUD
5 - STARTER MOTOR
6 - LOCK WASHER
7 - WIRE HARNESS CONNECTOR
8 - NUT
9 - SCREW AND WASHER (2)
DRSTARTING 8F - 33
STARTER MOTOR (Continued)
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. 14) 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.
(5) The coil ground terminal (85) is connected to
the electromagnet in the relay. On vehicles with
manual transmission, it is grounded at all times. On
vehicles with automatic transmission, it is grounded
through park/neutral position switch only when gear-
shift selector lever is in Park or Neutral positions.
Check for continuity to ground at cavity for relay ter-
minal 85. If not OK with manual transmission,
repair circuit to ground as required. If not OK with
automatic transmission, check for pen or short circuit
to park/neutral position switch and repair, if
required. If circuit to park/neutral position switch is
OK, refer toPark/Neutral Position Switchin 21,
Transmission.
Fig. 14 TYPE 1 RELAY
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
8F - 36 STARTINGDR
STARTER MOTOR RELAY (Continued)
HEATED SYSTEMS
TABLE OF CONTENTS
page page
HEATED GLASS........................... 1
HEATED MIRRORS......................... 6HEATED SEAT SYSTEM..................... 7
HEATED GLASS
TABLE OF CONTENTS
page page
HEATED GLASS
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING - REAR WINDOW
DEFOGGER SYSTEM...................2
REAR WINDOW DEFOGGER RELAY
DESCRIPTION..........................2
OPERATION............................3REMOVAL.............................3
INSTALLATION..........................4
REAR WINDOW DEFOGGER SWITCH
DESCRIPTION..........................4
OPERATION............................4
REAR WINDOW DEFOGGER GRID
STANDARD PROCEDURE - GRID LINE AND
TERMINAL REPAIR.....................4
HEATED GLASS
DESCRIPTION
CAUTION:Grid lines can be damaged or scraped off
with sharp instruments. Care should be taken in
cleaning glass or removing foreign materials, decals
or stickers. Normal glass cleaning solvents or hot
water used with rags or toweling is recommended.
The rear window defogger system consists of a
back glass with two vertical electrical bus bars linked
by a series of grid lines fired onto the inside surface
of the optional heated rear window.
The rear window defogger system is turned On or
Off by a switch and a timing circuit integral to the
A/C-heater control located at the center of the instru-
ment panel.
Circuit protection is provided by a cartridge fuse
located in the power distribution center (PDC) for the
heated grid circuit, and a fuse located in the fuse
block for the control circuit.
OPERATION
The rear window defogger system is turned on by a
momentary switch located in the A/C-heater control
on the instrument panel. When the rear windowdefogger switch is pressed to the On position, current
is directed through the rear window defogger relay to
the rear defogger grid lines. The heated grid lines
heat the rear glass to help clear the rear window sur-
face of fog or frost.
A yellow indicator above the switch will illuminate
to indicate when the rear window defogger system is
turned on. The A/C-heater control contains the rear
window defogger system control circuitry.
NOTE: The rear window defogger turns off automat-
ically after approximately 10 minutes of initial oper-
ation. Each following activation cycle of the
defogger system will last approximately ten minutes
also.
The rear window defogger system will be automat-
ically turned off after a programmed time interval of
about ten minutes. After the initial time interval has
expired, if the defogger switch is pressed to the On
position again during the same ignition cycle, the
rear window defogger system will automatically turn
off after about ten minutes also.
The rear window defogger system will automati-
cally shut off if the ignition switch is turned to the
Off position, or it can be turned off manually by
pressing the defogger switch a second time.
DRHEATED SYSTEMS 8G - 1
DIAGNOSIS AND TESTING - REAR WINDOW
DEFOGGER SYSTEM
For circuit descriptions and diagrams, refer to Rear
Window Defogger in Wiring Diagrams. The operation
of the electrically heated rear window defogger sys-
tem can be confirmed in one of the following man-
ners:
1. Turn the ignition switch to the On position.
While monitoring the instrument panel voltmeter, set
the defogger switch in the On position. When the
defogger switch is turned On, a distinct voltmeter
needle deflection should be noted.
2. Turn the ignition switch to the On position. Set
the defogger switch in the On position. The rear win-
dow defogger operation can be checked by feeling the
rear window or outside rear view mirror glass. A dis-
tinct difference in temperature between the grid lines
and the adjacent clear glass or the mirror glass can
be detected within three to four minutes of operation.
3. Using a 12-volt DC voltmeter, contact the rear
glass heating grid terminal A (right side) with the
negative lead, and terminal B (left side) with the pos-
itive lead (Fig. 1). The voltmeter should read battery
voltage.
The above checks will confirm system operation.
Illumination of the defogger switch indicator lamp
means that there is electrical current available at the
output of the rear window defogger logic and timer
circuitry, but does not confirm that the electrical cur-
rent is reaching the rear glass heating grid lines.
If the defogger system does not operate, the prob-
lem should be isolated in the following manner:(1) Confirm that the ignition switch is in the On
position.
(2) Make sure that the rear glass heating grid feed
and ground wires are connected to the glass. Confirm
that the ground wire has continuity to ground.
(3) Check the fuses in the power distribution cen-
ter (PDC) and in the junction block. The fuses must
be tight in their receptacles and all electrical connec-
tions must be secure.
When the above steps have been completed and the
rear glass heating grid is still inoperative, one or
more of the following could be faulty:
²Rear window switch in the A/C-heater control..
²Rear window grid lines (all grid lines would
have to be broken or one of the feed wires discon-
nected for the entire system to be inoperative).
If setting the defogger switch to the On position
produces a severe voltmeter deflection, check for a
short circuit between the rear window switch defog-
ger relay output and the rear glass heating grid.
REAR WINDOW DEFOGGER
RELAY
DESCRIPTION
The rear window defogger relay (Fig. 2) is a Inter-
national Standards Organization (ISO) micro-relay.
Relays conforming to the ISO specifications have
common physical dimensions, current capacities, ter-
minal patterns, and terminal functions. The ISO
micro-relay terminal functions are the same as a con-
ventional ISO relay. However, the ISO micro-relay
terminal pattern (or footprint) is different, the cur-
rent capacity is lower, and the physical dimensions
are smaller than those of the conventional ISO relay.
The rear window defogger relay is located in the
power distribution center (PDC) in the engine com-
partment. Refer to the PDC label for rear window
defogger relay identification and location.
The black, molded plastic case is the most visible
component of the rear window defogger relay. Five
male spade-type terminals extend from the bottom of
the base to connect the relay to the vehicle electrical
system, and the ISO designation for each terminal is
molded into the base adjacent to each terminal. The
ISO terminal designations are as follows:
²30 (Common Feed)- This terminal is con-
nected to the movable contact point of the relay.
²85 (Coil Ground)- This terminal is connected
to the ground feed side of the relay control coil.
²86 (Coil Battery)- This terminal is connected
to the battery feed side of the relay control coil.
²87 (Normally Open)- This terminal is con-
nected to the normally open fixed contact point of the
relay.
Fig. 1 Grid Line Test - Typical
1 - VIEW FROM INSIDE VEHICLE
2 - REAR WINDOW DEFOGGER
3 - BUS BARS
4 - VOLTAGE FEED (A)
5 - VOLTMETER
6 - MID-POINT (C)
7 - PICK-UP LEADS
8 - GROUND (B)
8G - 2 HEATED GLASSDR
HEATED GLASS (Continued)
SPECIFICATIONS
SPECIFICATIONS - TORQUE - IGNITION
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Camshaft Position Sensor
- 3.7L V-6 Engine12 - 106
Camshaft Position Sensor
- 4.7L V-8 Engine12 - 106
Camshaft Position Sensor
- 5.7L V-8 Engine12 9 105
Crankshaft Position
Sensor - 3.7L V-6 Engine28 21 205
Crankshaft Position
Sensor - 4.7L V-8 Engine28 21 205
Crankshaft Position
Sensor - 5.7L V-8 Engine12 9 105
Ignition Coil Mounting -
3.7L V-6 Engine8-70
Ignition Coil Mounting -
4.7L V-8 Engine8-70
Ignition Coil Mounting -
5.7L V-8 Engine12 9 105 ( 20)
* Knock Sensor - 3.7L V-6
Engine20 15 176
* Knock Sensor - 4.7L V-8
Engine20 15 176
* Knock Sensor - 5.7L V-8
Engine20 15 176
Spark Plugs - 3.7L V-6
Engine27 20 -
Spark Plugs - 4.7L V-8
Engine27 20 -
** Spark Plugs - 5.7L V-8
Engine18 ( 3) 13 ( 2) -
* Do not apply any sealant, thread-locker or adhesive to bolts. Poor sensor performance may result.
** Torque critical tapered design. Do not exceed 15 ft. lbs.
DRIGNITION CONTROL 8I - 3
IGNITION CONTROL (Continued)
CAMSHAFT POSITION SENSOR
DESCRIPTION
3.7L V-6
The Camshaft Position Sensor (CMP) on the 3.7L
6-cylinder engine is bolted to the right-front side of
the right cylinder head.
4.7L V-8
The Camshaft Position Sensor (CMP) on the 4.7L
V-8 engine is bolted to the right-front side of the
right cylinder head.
5.7L V-8
The Camshaft Position Sensor (CMP) on the 5.7L
V-8 engine is located below the generator on the tim-
ing chain / case cover on the right/front side of
engine.
5.9L Diesel
The Camshaft Position Sensor (CMP) on the 5.9L
diesel engine is located below the fuel injection
pump. It is bolted to the back of the timing gear
cover.
OPERATION
3.7L V-6
The Camshaft Position Sensor (CMP) sensor on the
3.7L V-6 engine contains a hall effect device referred
to as a sync signal generator. A rotating target wheel
(tonewheel) for the CMP is located at the front of the
camshaft for the right cylinder head (Fig. 6). This
sync signal generator detects notches located on a
tonewheel. As the tonewheel rotates, the notches
pass through the sync signal generator. The signal
from the CMP sensor is used in conjunction with the
Crankshaft Position Sensor (CKP) to differentiate
between fuel injection and spark events. It is also
used to synchronize the fuel injectors with their
respective cylinders.
When the leading edge of the tonewheel notch
enters the tip of the CMP, the interruption of mag-
netic field causes the voltage to switch high, result-
ing in a sync signal of approximately 5 volts.
When the trailing edge of the tonewheel notch
leaves then tip of the CMP, the change of the mag-
netic field causes the sync signal voltage to switch
low to 0 volts.
4.7L V-8
The CMP sensor on the 4.7L engine contains a hall
effect device called a sync signal generator to gener-
ate a fuel sync signal. This sync signal generator
detects notches located on a tonewheel. The tone-wheel is located at the front of the camshaft for the
right cylinder head (Fig. 7). As the tonewheel rotates,
the notches pass through the sync signal generator.
The pattern of the notches (viewed counter-clockwise
from front of engine) is: 1 notch, 2 notches, 3 notches,
3 notches, 2 notches 1 notch, 3 notches and 1 notch.
The signal from the CMP sensor is used in conjunc-
tion with the crankshaft position sensor to differenti-
ate between fuel injection and spark events. It is also
used to synchronize the fuel injectors with their
respective cylinders.
5.7L V-8
The CMP sensor is used in conjunction with the
crankshaft position sensor to differentiate between
fuel injection and spark events. It is also used to syn-
chronize the fuel injectors with their respective cylin-
ders. The sensor generates electrical pulses. These
pulses (signals) are sent to the Powertrain Control
Module (PCM). The PCM will then determine crank-
shaft position from both the camshaft position sensor
and crankshaft position sensor.
The tonewheel is located at the front of the cam-
shaft (Fig. 8). As the tonewheel rotates, notches (Fig.
8) pass through the sync signal generator.
When the cam gear is rotating, the sensor will
detect the notches. Input voltage from the sensor to
the PCM will then switch from a low (approximately
0.3 volts) to a high (approximately 5 volts). When the
sensor detects a notch has passed, the input voltage
switches back low to approximately 0.3 volts.
Fig. 6 CMP OPERATION- 3.7L V-6
1 - NOTCHES
2 - RIGHT CYLINDER HEAD
3 - CMP
4 - TONEWHEEL (TARGET WHEEL)
DRIGNITION CONTROL 8I - 7
OPERATION
3.7L V-6
Battery voltage is supplied to the 6 individual igni-
tion coils from the ASD relay. The Powertrain Con-
trol Module (PCM) opens and closes each ignition coil
ground circuit at a determined time for ignition coil
operation.
Base ignition timing is not adjustable.By con-
trolling the coil ground circuit, the PCM is able to set
the base timing and adjust the ignition timing
advance. This is done to meet changing engine oper-
ating conditions.
The ignition coil is not oil filled. The windings are
embedded in an epoxy compound. This provides heat
and vibration resistance that allows the ignition coil
to be mounted on the engine.
Because of coil design, spark plug cables (second-
ary cables) are not used with the 3.7L V-6 engine.
4.7L V-8
Battery voltage is supplied to the 8 individual igni-
tion coils from the ASD relay. The Powertrain Con-
trol Module (PCM) opens and closes each ignition coil
ground circuit at a determined time for ignition coil
operation.
Fig. 17 IGNITION COIL LOCATION - 4.7L V-8
1 - IGNITION COIL
2 - COIL ELECTRICAL CONNECTOR
3 - COIL MOUNTING STUD/NUT
Fig. 18 IGNITION COIL - 5.7L V-8
1 - IGNITION COIL
2 - MOUNTING BOLTS (2)
3 - BOOT TO SPARK PLUG
Fig. 19 IGNITION COIL R/I Ð 5.7L V-8
1 - SLIDE LOCK (SLIDE OUTWARD TO UNLOCK)
2 - SPARK PLUG CABLE (TO OPPOSITE CYLINDER BANK
SPARK PLUG)
3 - RELEASE LOCK / TAB (PUSH HERE)
4 - ELEC. CONNECTOR
5 - IGNITION COIL
6 - COIL MOUNTING BOLTS (2)
7 - SPARK PLUG CABLE (TO OPPOSITE CYLINDER BANK
IGNITION COIL)
8I - 12 IGNITION CONTROLDR
IGNITION COIL (Continued)