
8D
- 18
IGNITION
SYSTEMS
•
COMPONENT REMGWAL/INSTALLATION
INDEX
page
Automatic
Shut Down (ASD) Relay
18
Camshaft
Position
Sensor
, 18
Crankshaft Position
Sensor
18
Distributor
Service
20
Engine
Coolant Temperature
Sensor
20
General
Information
18
Ignition
Coil
21
page
Intake
Manifold Charge
Air
Temperature
Sensor
. 22
Manifold Absolute Pressure (MAP)
Sensor
..... 22
Oxygen
(02)
Sensor
22
Powertrain
Control
Module (PCM)
22
Spark
Plug Secondary Cables
24
Spark
Plugs
23
Throttle
Position
Sensor
(TPS)
24
GENERAL
INFORMATION
This section
of the
group, Component Removal/In
stallation, will discuss
the
removal
and
installation
of ignition system components. For basic ignition system diagnostics
and
service
adjustments, refer
to the
Diagnostics/Service Proce
dures section
of
this group. For system operation
and
component identification,
refer
to the
Component Identification/System Opera
tion section
of
this group.
AUTOMATIC
SHUT DOWN
(ASb)
RELAY
The automatic shut down
(ASD)
relay
is
located
in
the engine compartment
(Fig. 1).
TORQUE CONVERTER
CLUTCH RELAY
A/C
CLUTCH RELAY STARTER RELAY
AUTO
SHUTDOWN RELAY FUEL PUMP RELAY DATA UNK
CONNECTOR POWERTRAIN
CONTROL
MODULE
J9314-164
Fig.
1
Auto
Shut Down
Relay
REMOVAL
(1) Disconnect negative battery cable
at
battery.
(2)
Remove
the
relay
by
pulling from connector.
INSTALLATION
(1) Check
the
terminals
in the
relay connector
for
corrosion
or
damage before installation.
(2)
Push
the
relay into
the
connector.
CAMSHAFT POSITION SENSOR
The camshaft position sensor
is
located
in the
dis
tributor
(Fig. 2).
REMOVAL
Distributor removal
is not
necessary
to
remove
camshaft position sensor.
CAMSHAFT POSITION
SENSOR
SYNC
SIGNAL
GENERATOR
DISTRIBUTOR
ASSEMBLY
J9314-82
Fig.
2
Camshaft Position Sensor—Typical
(1) Disconnect negative battery cable
at
battery.
(2)
Remove distributor
cap
from distributor
(two
screws).
(3) Disconnect camshaft position sensor wiring
harness from main engine wiring harness.
(4) Remove distributor rotor from distributor shaft.
(5)
Lift
the
camshaft position sensor assembly from
the distributor housing
(Fig. 2).
INSTALLATION
(1) Install camshaft position sensor
to
distributor.
Align sensor into notch
on
distributor housing.
(2)
Connect wiring harness.
(3) Install rotor.
(4) Install distributor
cap.
Tighten mounting
screws.
CRANKSHAFT
POSITION SENSOR
REMOVAL The sensor
is
bolted
to the top of the
cylinder block
near
the
rear
of
right cylinder head
(Fig. 3).

•
INSTRUMENT PANEL
AND
GAUGES
8E - 5
CLUSTER
AND
GAUGE TEST
PROCEDURES
INDEX
page
Fuel Gauge
Circuit
Test
9
Fuel Tank Sending
Unit
Test
5
Oil Pressure Gauge
Circuit
Test
..............
9
Sending
Unit
(Sensor) Test
5
page
Speedometer
10
Temperature
Gauge
Circuit
Test
8
Voltage Gauge
Circuit
Test
10
Warning Lamp System Tests
6
CAUTION:
Disconnect
battery
negative cable,
in
en
gine compartment, before servicing instrument panel. When power
is
required
for
test purposes,
connect
battery
cable
(for
test only).
Disconnect battery negative cable after test
and before continuing service procedures.
SENDING
UNIT
(SENSOR) TEST
When
a
problem occurs with
a
cluster gauge,
be
fore disassembling
the
cluster
to
check
the
gauge, check
for a
defective sending unit (sensor)
or
wiring.
(1) Sending units
and
wiring
can be
checked
by
grounding
the
connector leads,
at the
sending unit,
in
the
vehicle.
CAUTION:
When connecting
an
input
terminal
to
ground,
Do Not
leave
the
connection grounded
for
more than
a
few
seconds.
(2) With
the
ignition
in the ON
position;
a
grounded input will cause
the oil,
fuel
or
tempera
ture gauge
to
read
at or
above maximum.
FUEL TANK SENDING
UNIT
TEST
(1) Disconnect wire from terminal
on
fuel tank
sending unit (Fig.
1).
FUEL PUMP SUPPLY
INPUT
TO
GAUGE
SENDING
UNIT
GROUND
FUEL PUMP GROUND
J928E-49
Fig.
1
Fuel
Tank
Sending
Connector
Terminals
(2) Connect wire
to a
known good sending unit.
(3) Connect
a
jumper wire between sending unit
fuel pick
up
tube
and a
good ground.
(4) Check fuel gauge
as
described
in
following
steps.
Allow
at
least three minutes
at
each test point
for gauge
to
settle. Lightly tapping instrument clus
ter
may
help position pointer.
FUEL GAUGE SYSTEM DIAGNOSIS
FUEL GAUGE SYSTEM DIAGNOSIS FUEL GAUGE
DOES
NOT
READ
FULL FAULTY PRINTED
CIRCUIT BOARD FUEL GAUGE
INOPERATIVE OR ERRATIC FUEL GAUGE
INACCURATE
E
1
I
CHECK
FAULTY WIRING
OR
TANK DEFORMED
TANK
NOT
FULL COMPONENTS
CHECK
CHECK
ALL WIRING INCLUDING GROUND
i
FAULTY FUEL GAUGE SENDING
UNIT
i 1
FUEL
C
1
DOES
1
READ
1
pAUGE
I
>N0?
1
EMPTY
1
r
TANK
NOT
EMPTY
CHECK
PROPER
ALIGNMENT
OF PICKUP AND
SENDER
ASSEMBLY.
REFER
TO
GROUP
14
FAULTY FUEL
GAUGE
J908E-74

WINDSHIELD
WIPER MOTOR
TO RIGHT
HEADLAMP
PARK/TURN
SIGNAL LAMP TO FUSIBLE LINK
CIRCUITS
TO VEHICLE SPEED
CONTROL SEE VIEW
Z
EEMC
RELAY
LEFT
HEADLAMP
GROUND
ENGINE
STARTER
A/C RELAY
COMPRESSOR
CLUTCH RELAY AUTOMATIC SHUT
DOWN RELAY
FUEL PUMP RELAY
BULKHEAD
DISCONNECT
A/C
LOW
PRESSURE
SWITCH
SIDE
MARKER LAMP
TO UNDERHOOD LAMP WIRING
VEHICLE
SPEED
CONTROL
SERVO
POWERTRAIN
CONTROL MODULE
A/C
CYCLING SWITCH TO BLOWER
MTR &
WINDSHIELD
WASHER
MTR
VIEW
IN
DIRECTION OF ARROW
Z
VIEW
IN
DIRECTION
OF ARROW
W a
o
>
o 30
>
2
m
J938W-99
Fig.
17
Engine
Compartment Wiring 3.9L, 5.2L, and 5.9L Gas
Engines

FUEL
INJECTOR
#6
FUEL
INJECTOR
#4
FUEL
INJECTOR
#2
BEYOND
THIS
POINT
SEE
VIEW
Z
EGR
SOLENOID/
TRANSDUCER
ASSEMBLY
A/C
COMPRESSOR
CLUTCH
GENERATOR
GROUND
POWER
STEERING
PUMP
AAAP
SENSOR
THROTTLE
EVAP/
POSITION
PURGE
(SENSOR)
SOLENOID IDLE
AIR
CONTROL MOTOR
TO
A/C
COMPRESSOR
CLUTCH
DISTRIBUTOR
IGNITION
COIL
ENGINE
COOLANT
TEMPERATURE
ENGINE
COOLANT
SENSOR
(PCM)
TEMPERATURE
SENSOR
(GAUGE)
ENGINE
OIL
PRESSURE
SENDING
UNIT/
SWITCH
DISTRIBUTOR
CONNER ,NJECTOR#1
INJECTOR
#3
VIEW
IN
DIRECTION OF ARROW
1
FUEL
INJECTOR
#5
TO
'TRANSMISSION
WIRING
J938W-85 INS
m
a
o
>
o
>
2
m Fig. 23 Engine
Wiring
3.9L MPI Engine

FUEL
INJECTOR
#8
FUEL
INJECTOR #4 FUEL
INJECTOR
#2
EGR
SOLENOID/
TRANSDUCER
DISTRIBUTOR
IGNITION
COIL
THROTTLE
BODY
CHARGE
AIR
TEMPERATURE
SENSOR
BEYOND
THIS
POINT
SEE
VIEW,
Z
TO
A/C
COMPRESSOR
CLUTCH ^DISTRIBUTOR
GENERATOR
GROUND
POWER
STEERING
PUMP ENGINE
OIL
PRESSURE
SENDING
UNIT/SWITCH
VIEW
IN
DIRECTION OF ARROW
Y
TO TRANSMISSION WIRING
THROTTLE
POSITION
(SENSOR)
IDLE AIR
CONTROL MOTOR
GENERATOR
ENGINE COOLANT
TEMPERATURE
SENSOR
(PCM)
ENGINE
COOLANT
TEMPERATURE
SENSOR
(GAUGE)
MAP
SENSOR
FUEL
INJECTOR
#3
EVAP/PURGE
SOLENOID
FUEL
INJECTOR #7
FUEL
INJECTOR.
#5
FUEL
INJECTOR
#1
A/C
CLUTCH VIEW
IN
DIRECTION
OF ARROW
Z
J938W-86
Fig.
24 Engine Wiring 5.2L and 5.9L MPI Engine o
>
30
>
2
w
oo !\3

8W
- 38
WIRING
DIAGRAMS
• Wiring Diagram Name Sheet Number
EMCC
Relay
11
EMCC
Solenoid
11
Ground
11
EMCC
Relay
with Gas
Engine
11,16
EMCC
Solenoid
with Gas
Engine
11,12
Engine
Oil
Pressure Sending
Unit
.27,28
Engine
Starter
Motor
7,9
Engine
Starter
Relay
.7,9
Engine
Starter
System 1,7,8,9 Back-Up Lamp
Switch
.7,9
Bypass
Jumper
(Clutch
Pedal
Position)
8
Clutch
Pedal
Position
Switch
8
Fuse
. 7,9
Motor
7,9
Park/Neutral
Position
Switch
. .7,9
Relay
7,9
Engine Temp Sending
Unit
.
.27,28
Flasher-Hazard Warning
.56
Flasher-Turn Signal
56
Four Wheel
Drive
Indicator
Lamp
13
Front
End
Lighting
. .
.43,44
Front
End
Lighting
(Canada) 45,46
Fuel
Gauge
81,82
Fuel
Tank Gauge
Level
Sending
Unit
Diesel Engine
77
Fuel
Tank Gauge
Level
Sending
Unit
with Gas
Engine
78
Fuel
Heater
Diesel Engine
24
Fuel
Solenoid Diesel Engine
.24
Fuse
Application
Chart
1,2
Fuse
Block Module
and
Relay Bank
82
Fuses
Fuse
1 2,36
Fuse
2
.........
2,10,12,13,14,58,77,78
Fuse
3
2,7,9,10,39
Fuse
4
1,30,47
Fuse
5
1,77,78
Fuse
6
......
.1,73
Fuse
7
1,10,52
Fuse
8
.2,10,61,63
Fuse
9
.2,10,31,33,56
Fuse
10
.2,10,54,55
Fuse
11
2,10,66,67,69
Fuse
12
2,10,71
Fuse
13 1,56
Fuse
14
1,47,52,61,63
Fuse
15
1,49,51,52,61,63,75
Fusible Links 1,2,3,4,5,6,21
Gas
Engine
Wiring
Connector
89
Gauge-Fuel .77,78
Generator
.4,6
Glove
Box
Lamp
Switch
52
Hazard Warning System
. .56
Headlamp Dimmer
Switch
47
Headlamp
Switch
1,47
Headlamp
Switch
Controlled
Interior
Lamps
Headlamps 43,44,
Heated
Rear Window
(Sport
Utility)
Heater
Motor
Resistor
Heater
System Wiring Diagram Name Sheet Number
Horn System
30
Identification
Lamps-Dual Rear Wheels
41,42
Identification
Lamps-Roof Mounted
. 40
Ignition
Coil
.16
Ignition
Switch
.2,10
Ignition
Switch
System
10
Ignition
System (Gas Engine)
.........
.15,16,17,18,19,20
Automatic
Shut Down Relay
.16
Camshaft
Position
Sensor
20
Crankshaft
Position
Sensor
.18
Data
Link
Connector
* . . .17
Engine Coolant Temp
Sensor
20
EVAP
Purge Solenoid
16
Exhaust Gas
Recirculation
Solenoid
16
Fuel
Pump Relay
.16
Heated
Oxygen
Sensor
. . . 17
Idle
Air
Control
Motor
.19
Ignition
Coil
.15
Injectors
.15
Intake
Air
Temp
Sensor
. .20
Map
Sensor
. .20
Powertrain
Control
Module .15,16,17,18,19,20
Throttle
Position
(Sensor)
.18
Vehicle
Speed
Sensor
.20
Ignition
Time
Delay Relay
49
Injectors
.15 Intermittent
Wiper
System .53,54
Control
Unit
.54 Intermittent
Windshield
Wiper
Motor
54
Windshield
Washer Pump
Motor
53
Wiper
Switch
53
Key-In
Switch
49
Key-In Warning Buzzer 77,78
Lamps
Air-Conditioning
and
Heater
Switch
Lamp
48
Ash
Receiver .48,52 Back-Up Lamps
......
79,80,81
Cargo Lamp
.
.49,50 Clearance Lamps-Dual Rear Wheels .41,42
Clearance Lamps Roof Mounted
.40
Cluster
Illumination
Lamps
.
.57,58,59
Dome Lamp
50,51
Four Wheel
Drive
Indicator
.13
Glove
Box
Lamp
52
Headlamp-Left
43,45 Headlamp-Right 44,46
Headlamp
Switch
Controlled
Interior
Lamps
. 48
Heater
Switch
Lamp
.48
High Beam
Indicator
Lamp
.59
Identification
Lamp
.
.40,41
Ignition
Switch
Lamp
.49
Instrument
Panel
Illumination
Lamps
.
.57,58,59
License Lamp
. . . 80
.
.48 Low
Engine
Oil
Pressure Lamp
59
45,46
Map
Lamp
49
.
.39
Parking
Lamp-Left
Front
43,45
66,67 Parking Lamp-Right
Front
44,46 .
.66
Rear
End
Lighting
System .79,80,81

WIRING
DIAGRAMS
8W - 39
Wiring
Diagram
Name
Sheet
Number
Service Reminder Lamp .58
Side
Marker Lamp
Left
Front
43,45
Side
Marker Lamp Right
Front
. .44,46
Stop
Lamp-Left
Rear 79,81 Stop Lamp-Right Rear 80,81
Tachometer
.48
Tail
Lamp-Left
Rear .79,81
Tail
Lamp-Right Rear 80,81
Turn
Signal
Indicator
Lamps .79,80,81
Turn
Signal
Lamp-Left
Front
43,45
Turn
Signal Lamp-Right
Front
44,46
Turn
Signal
Lamp-Left
Rear .79,81
Turn
Signal Lamp-Right Rear 80,81
Underhood Lamp 29
Left
Printed
Circuit
Board .59
Left
Printed
Circuit
Board Connector 60
Liftgate
Ajar
Switch
51
Map
Lamp and Cargo Lamps .49
Message
Center
(Diesel Engine) 57
Message
Center
(Gas Engine) .58
Modules
Daytime
Running Lamp . .46
Intermittent
Wiper
.54
Key
-In
77,78
Seat
Belt
Warning 77,78
Motors Blower-A/C
with
Diesel Engine .69
Blower-A/C
with
Gas Engine 67
Blower-Heater
.66
Engine
Starter
with
Diesel Engine . .7 Engine
Starter
with
Gas Engine 9
Heater
Blower
66,67
Idle
Air
Control
............... ........
.19
Intermittent
Windshield
Wiper
54
Power Door
Lock-Left
.73
Power Door Lock-Right 74
Power
Mirror
Left
75
Power
Mirror
Right .76 Power
Window-Left
71
Power Window-Right .72
Windshield Washer Pump 53
Neutral/Park
Position
Switch
with
Diesel Engine 7
Neutral/Park
Position
Switch
with
Gas Engine 9
Oil Pressure Sending
Unit
with
Diesel Engine 27
Oil Pressure Sending
Unit
with
Gas Engine 28 Oil Pressure
Switch
with
Diesel Engine 27
Oil Pressure &
Temperature
System (Diesel) 27 Oil Pressure &
Temperature
System (Gas) . 28
Oil Pressure Warning Lamp • -59 Parking Brake
Switch
.31,33 Power Door Lock System . . 73,74
Left
Door Motor . .73
Left
Door
Switch
. 73
Right Door Motor . -74 Right Door
Switch
74
Power
Mirrors
75,76
Fuse
75
Left
Motor 75
Wiring
Diagram
Name
Sheet
Number
Right Motor 76
Switch
76
Powertrain
Control
Module
........
.11,12,14,15,16,17,18,
19,20,21,22,23,24,35,37
Powertrain
Control
Module Connector .83,84
Power Window System 71,72
Circuit
Breaker 71
Left
Door
Switch
71
Left
Motor 71 Right Door
Switch
72
Right Motor 72
Printed
Circuit
Board Connectors 60
Radio-4 Speakers 61,62,63,64
Radio-2 Speakers 65
Rear
Lighting
System 79,80
Rear
Wheel
Anti-Lock
Brake System (Diesel) 33,34 Brake Warning Lamp
Switch
.34 Data
Link
Connector 33
Dual Solenoid
Hydraulic
Valve 34
Electronic
Vacuum
Sensor
34
Fuse
.33 Module 33 Park Brake
Switch
33
Rolls Test Connector .33 Resistor .34
Sensor
. .34 Stop Lamp
Switch
. .34
Rear
Wheel
Anti-Lock
Brake System (Gas) . .31,32 Brake Warning Lamp
Switch
.32
Data
Link
Connector .31 Dual Solenoid
Hydraulic
Valve 32
Fuse
31
Module 31 Park Brake
Switch
31
Resistor 32 Rolls Test Connector 31
Sensor
32
Stop Lamp
Switch
32
Relays
Air
Heater
(Diesel Engine) .21
Automatic
Shut Down
with
Diesel Engine 22
Automatic
Shut Down
with
Gas Engine 16
EMCC
Relay 11 Engine
Starter
Relay .7,9
Fuel Pump 16
Horn 30
Ignition
Lamp
Time
Delay 49
Wide Open
Throttle
Cut-Out Diesel Engine 70
Wide Open
Throttle
Cut-Out Gas Engine 68
Resistor 24,32,34,36,38
Right
Printed
Circuit
Board 59 Right
Printed
Circuit
Board Connector 60 Rolls Test Connector .31,33
Seat
Belt
Warning System 77,78
Sending
Units
Fuel Gauge-Diesel Engine 77 Fuel
Gauge-Gas
Engine 78
Oil-Diesel Engine 27

WIRING
DIAGRAMS
8W - 43
FUSIBLE
LINK
(18GY)
12BK/RD
FUSIBLE
LINK
(200R)
(LEFT
FRONT
WHEELHOUSE) HEATED
REAR
WINDOW
SH
39
FUSIBLE
LINK
(200R)
(LEFT
FRONT
WHEELHOUSE)
I—A22
12BK/0R
IT
1
30
AMPS
J CIRCUIT
,—h BREAKER —P CAVITY
#12
-A22
12BK/0R-
RUN ONLY
IGNITION
SWITCH
SH
10
A31
14BK/WT
RUN
AND ACC
F21
12TN
POWER WINDOW
SH
71
FUSE
#11
30 AMP
CI
12DG
A/C
AND
HEATER BLOWER MOTOR
SH
66.67.69
S
FUSE
#10
10*ZJ20
AMP
O
FUSE
#8
310 AMP
-A41
14YL-
ENGINE
STARTER
SYSTEM
SH
7.8.9
A21
14DB
FUSE
#1
3
2 AMP
RUN
AND
START
V34
20WT/RD
A2I
14DB
VEHICLE
SPEED
CONTROL (GAS)
SH
36
VEHICLE
SPEED
CONTROL (DIESEL)
SH
38
FUSE
#3
20 AMP
F20
18WT
BACK-UP
LAMP
SH
79.80
HEATER REAR WINDOW
SH
39
G5
20DB/WT
TO
4tART
D
FUSE
# 2
3
5 AMP
LAMP LOW
FUSE
#9
120 AMP
V6
18DB
WINDSHIELD WIPER
SYSTEM
SH
54.55
RADIO
AND
CLOCK
SH
61.63.65
L5
18RD
i
TURN SIGNAL FLASHER
SH
56
TACHOMETER
PROVISIONS
SH
48
REAR
WHEEL ANTI-LOCK
MODULE
SH
31.33
AUTOMATIC
SHUT DOWN
RELAY
SH
16.22
TRANSMISSION
OVERDRIVE
SOLENOIDS
SH
12.14
FUEL PUMP RELAY
SH
16
GENERATOR
SH
4
VACUUM SENSOR
SH
34
AIR SWITCHING
SOLENOIDS
SH
16
PMC
SH
16
AIR HEATER CONTROLLER
SH
21
WOT RELAY
SH
68.70
A/C
ELECTRONIC CYCLING SWITCH
SH
68.70
3.R.L.
MODULE
SH
46
EMCC
RELAY
SH
11
FUEL HEATER AND PUMP
SH
24
WAIT
TO
START
SH
57
FUEL LAMP
SH
57
GAUGES
SH
59
BRAKE
LAMP
SH
57.58
SEAT
BELT LAMP AND BUZZER
SH
77 78
WATER
IN
FUEL LAMP
SH
57
4
WHEEL DRIVE
INDICATOR LAMP
SH
13
LOW ENGINE
OIL
LAMP
SH
59
MALFUNCTION
INDICATOR LAMP
SH
59
ANTI-LOCK LAMP
SH
57 58
LIFTGATE OPEN LAMP
SH
58
TRANSMISSION
CONTROL MODULE
SH
12.14
SERVICE
REMINDER INDICATOR LAMP
SH
58
J938W-11
FUSE
APPLICATION
CHART
AD
2