
BULB APPLICATIONÐXJ VEHICLES
GENERAL INFORMATION
The following Bulb Application Table lists the lamp
title on the left side of the column and trade number
or part number on the right.
CAUTION: Do not use bulbs that have a higher can-
dle power than the bulb listed in the Bulb Applica-
tion Table. Damage to lamp can result.
Do not touch halogen bulbs with fingers or other
oily surfaces. Bulb life will be reduced.
EXTERIOR LAMPSÐXJ
Back-up .................................................................1156
Center High Mounted Stoplamp ..........................922
Fog ............................................................................H3
Front Side Marker .................................................194
Headlamp/Sealed Beam....................................H6054
License Plate ..........................................................168
License Plate W/Outside Spare ..............................67
Park/Turn Signal ............................................2057NA
Tail/Stop ................................................................2057
Turn Signal ...........................................................1156
INTERIOR LAMPSÐXJ
Service procedures for most of the lamps in the in-
strument panel, Instrument cluster and switches are
located in Group 8E, Instrument Panel and Gauges.
Some components have lamps that can only be ser-
viced by an Authorized Service Center (ASC) after
the component is removed from the vehicle. Contact
local dealer for location of nearest ASC.
Cargo .......................................................................561
Dome .......................................................................561
Dome/Reading.........................................................906Glove Compartment ...............................................194
Overhead Console ..................................................912
Under Hood ............................................................105
Vanity Mirror ...........................................................74
Underpanel Courtesy.............................................168
INDICATOR LAMPS
Service procedures for most of the lamps in the in-
strument panel, instrument cluster and switches are
located in Group 8E, Instrument Panel and Gauges.
A/C Control ...............................................................74
Airbag ........................................................................74
Anti-lock Brake ........................................................74
Ash Receiver .........................................................1891
Brake Warning .........................................................74
Check Engine ...........................................................74
Cigar Lighter ............................................................53
Diesel Wait ...............................................................74
Fasten Seat Belts ....................................................74
Four Wheel Drive ....................................................74
Generator ................................................................194
Generator/Diesel.......................................................74
Heater Control .........................................................74
High Beam..............................................................194
Illumination ............................................................194
Low Fuel .................................................................194
Low Washer Fluid....................................................74
Radio ......................................................................ASC
Rocker Switch...........................................................37
Seat Belt ...................................................................74
Transfer Case .........................................................658
Transmission Floor Shift.......................................658
Turn Signal.............................................................194
Shift ...........................................................................74
Water In Fuel ...........................................................74
8L - 18 LAMPSÐXJ VEHICLESJ

WIRING DIAGRAMSÐGENERAL INFORMATION
INDEX
page page
Circuit Identification......................... 1
Connector and Terminal Replacement........... 7
Connector Replacement..................... 6
Connectors............................... 2
Diode Replacement........................ 8
Electrostatic Discharge (ESC) Sensitive Devices . . . 2
General Information......................... 1
Intermittent and Poor Connections.............. 4
Notes, Cautions, and Warnings................ 1Symbols................................. 2
Take Outs................................ 2
Terminal Replacement....................... 8
Terminal/Connector RepairÐMolex Connectors.... 6
Troubleshooting Tests....................... 4
Troubleshooting Tools....................... 4
Troubleshooting Wiring Problems.............. 5
Wire Code Identification..................... 1
Wiring Repair............................. 6
GENERAL INFORMATION
This Group is divided into three stand alone sec-
tions; XJ, YJ, and XJ Right Hand Drive (XJ-RHD).
Separate circuit descriptions and wiring diagrams are
provided for each vehicle. Each section contains a
Contents list for the wiring diagrams and circuit de-
scriptions for that vehicle.
The complete XJ circuit descriptions and diagrams
are printed first, followed by those for the YJ and
then the XJ-RHD. The heading at the top of each
page identifies the vehicle covered in the section.
NOTES, CAUTIONS, and WARNINGS
Throughout this group additional important infor-
mation is presented in three ways; Notes, Cautions,
and Warnings.
NOTESare used to help describe how switches or
components operate to complete a particular circuit.
They are also used to indicate different conditions
that may appear on the vehicle. For example, an
up-to and after condition.
CAUTIONSare used to indicate information that
could prevent making an error that may damage the
vehicle.
WARNINGSprovide information to prevent per-
sonal injury and vehicle damage. Below is a list of
general warnings that should be followed any time a
vehicle is being serviced.
ALWAYS WEAR SAFETY GLASSES FOR EYE PRO-
TECTION.
USE SAFETY STANDS ANYTIME A PROCEDURE RE-
QUIRES BEING UNDER A VEHICLE.
BE SURE THAT THE IGNITION SWITCH ALWAYS IS
IN THE OFF POSITION, UNLESS THE PROCEDURE
REQUIRES IT TO BE ON.SET THE PARKING BRAKE WHEN WORKING ON
ANY VEHICLE. AN AUTOMATIC TRANSMISSION
SHOULD BE IN PARK. A MANUAL TRANSMISSION
SHOULD BE IN NEUTRAL.
OPERATE THE ENGINE ONLY IN A WELL-VENTI-
LATED AREA.
KEEP AWAY FROM MOVING PARTS WHEN THE EN-
GINE IS RUNNING, ESPECIALLY THE FAN AND BELTS.
TO PREVENT SERIOUS BURNS, AVOID CONTACT
WITH HOT PARTS SUCH AS THE RADIATOR, EX-
HAUST MANIFOLD(S), TAIL PIPE, CATALYTIC CON-
VERTER, AND MUFFLER.
DO NOT ALLOW FLAME OR SPARKS NEAR THE
BATTERY. GASES ARE ALWAYS PRESENT IN AND
AROUND THE BATTERY.
ALWAYS REMOVE RINGS, WATCHES, LOOSE
HANGING JEWELRY, AND LOOSE CLOTHING.
WIRE CODE IDENTIFICATION
Each wire shown in the diagrams contains a code
(Fig. 1) which identifies the main circuit, part of the
main circuit, gauge of wire, and color. The color is
shown as a two letter code which can be identified by
referring to the Wire Color Code Chart (Fig. 2).
CIRCUIT IDENTIFICATION
All circuits in the diagrams use an alpha/numeric
code to identify the wire and its function (Fig. 3). To
identify which circuit code applies to a system, refer
to the Circuit Identification Code Chart. This chart
shows the main circuits only and does not show the
secondary codes that may apply to some models.
JWIRING DIAGRAMSÐGENERAL INFORMATION 8W - 1

WIRING DIAGRAMS
CONTENTS
page page
8W-01 GENERAL INFORMATIONÐWIRING
DIAGRAMS.................... 8W-01-1
8W-10 FUSE/FUSE BLOCK........... 8W-10-1
8W-11 POWER DISTRIBUTION........ 8W-11-1
8W-15 GROUND DISTRIBUTION....... 8W-15-1
8W-20 CHARGING SYSTEM.......... 8W-20-1
8W-21 STARTING SYSTEM........... 8W-21-1
8W-30 FUEL/IGNITION.............. 8W-30-1
8W-31 TRANSMISSION CONTROLS.... 8W-31-1
8W-32 ANTI-LOCK BRAKES.......... 8W-32-1
8W-33 VEHICLE SPEED CONTROL..... 8W-33-1
8W-40 INSTRUMENT CLUSTER....... 8W-40-1
8W-41 HORN/CIGAR LIGHTER......... 8W-41-1
8W-42 AIR CONDITIONING/HEATER.... 8W-42-1
8W-44 INTERIOR LIGHTING.......... 8W-44-1
8W-47 AUDIO SYSTEM.............. 8W-47-18W-48 HEATED REAR WINDOW....... 8W-48-1
8W-49 OVERHEAD CONSOLE......... 8W-49-1
8W-50 FRONT LIGHTING............. 8W-50-1
8W-51 REAR LIGHTING............. 8W-51-1
8W-52 TURN SIGNALS.............. 8W-52-1
8W-53 WIPERS..................... 8W-53-1
8W-54 TRAILER TOW................ 8W-54-1
8W-60 POWER WINDOWS.......... 8W-60-1
8W-61 POWER DOOR LOCKS......... 8W-61-1
8W-62 POWER MIRRORS............ 8W-62-1
8W-63 POWER SEAT................ 8W-63-1
8W-70 SPLICE INFORMATION........ 8W-70-1
8W-80 CONNECTOR PIN OUTS....... 8W-80-1
8W-90 CONNECTOR LOCATIONS...... 8W-90-1
8W-95 SPLICE LOCATIONS........... 8W-95-1
HOW TO USE THIS GROUP
The purpose of this group is to show the electrical
circuits in a clear, simple fashion and to make trou-
bleshooting easier. Components that work together
are shown together. All electrical components used in
a specific system are shown on one diagram. The feed
for a system is shown at the top of the page. All
wires, connectors, splices, and components are shown
in the flow of current to the bottom of the page. Wir-
ing which is not part of the circuit represented is ref-
erenced to another page/section, where the complete
circuit is shown. In addition, all switches, compo-
nents, and modules are shown in theat rest posi-
tion with the doors closed and the key removed
from the ignition.
If a component is part of several different circuits,
it is shown in the diagram for each. For example, the
headlamp switch is the main part of the exterior
lighting, but it also affects the interior lighting and
the chime warning system.
It is important to realize that no attempt is
made on the diagrams to represent components
and wiring as they appear on the vehicle. For
example, a short piece of wire is treated the
same as a long one. In addition, switches and
other components are shown as simply as pos-
sible, with regard to function only.
The wiring diagram show circuits for all wheel-
bases. If there is a difference in systems or compo-
nents between wheel-bases, an identifier is placed
next to the component.
SECTION IDENTIFICATION
Sections in Group 8W are organized by sub-sys-
tems. The sections contain circuit operation descrip-
tions, helpful information, and system diagrams. The
intention is to organize information by system, con-
sistently from year to year.
CONNECTOR LOCATIONS
Section 8W-90 contains Connector Location illus-
trations. The illustrations contain the connector
number and component identification. Connector Lo-
cation charts in Section 8W-90 reference the illustra-
tion number for components and connectors.
Section 8W-80 shows each connector and the cir-
cuits involved with that connector. The connectors
are identified using the number on the Diagram
pages.
SPLICE LOCATIONS
Splice Location charts in Section 8W-70 show the
entire splice, and provide references to other sections
the splice serves.
Section 8W-95 contains illustrations that show the
general location of the splices in each harness. The
illustrations show the splice by number, and provide
a written location.
JWIRING DIAGRAMSÐXJ VEHICLES 8W - 1 - 1

POWER DISTRIBUTION
GENERAL INFORMATION
This section covers the Power Distribution Center
(PDC) and all circuits involved with it. For additional
information on system operation, refer to the appro-
priate section of the wiring diagrams.
DIAGRAM INDEX
Component Page
A/C Compressor Clutch Relay..............8W-11-3, 11
ABS Control Module.....................8W-11-6, 7
ABS Power Relay......................8W-11-3, 6
ABS Pump Motor Relay..................8W-11-3, 7
Automatic Shut Down Relay................8W-11-3, 9
Chime/Buzzer Module..................8W-11-10, 14
Circuit Breaker Cavity 16 (Fuse Block)..........8W-11-13
Combination Flasher......................8W-11-17
Daytime Running Lamp Module.............8W-11-5, 10
Diode D101............................8W-11-6
Engine Starter Motor Relay................8W-11-3, 4
Fuel Pump Relay.......................8W-11-3, 8
Fuse 1 (PDC)..........................8W-11-13
Fuse 3 (PDC)..........................8W-11-12
Fuse 4 (Fuse Block)......................8W-11-14
Fuse 4 (PDC)..........................8W-11-15
Fuse 5 (PDC)..........................8W-11-14
Fuse 6 (PDC)....................8W-11-4, 7, 10, 15
Fuse 7 (Fuse Block).......................8W-11-7
Fuse 7 (PDC)...........................8W-11-4
Fuse 8 (PDC)...........................8W-11-7
Fuse 9 (Fuse Block)......................8W-11-12
Fuse 9 (PDC)..........................8W-11-13
Fuse 10 (PDC)........................8W-11-6, 8
Fuse 11 (Fuse Block).....................8W-11-13
Fuse 11 (PDC).........................8W-11-10
Fuse 12 (PDC).........................8W-11-15Component Page
Fuse 13 (PDC)..........................8W-11-4
Fuse 14 (PDC)..........................8W-11-8
Fuse 15 (Fuse Block).....................8W-11-14
Fuse 15 (PDC)..........................8W-11-8
Fuse 16 (PDC).........................8W-11-12
Fuse 17 (Fuse Block).....................8W-11-10
Headlamp Delay Module.................8W-11-10, 14
Headlamp Switch........................8W-11-14
Headlamp Dimmer Switch..................8W-11-14
Horn Rear Window Relay..................8W-11-17
Horn Relay............................8W-11-17
Ignition Switch...................8W-11-4, 7, 10, 15
In-Line Circuit Breaker (Stop Lamp Relay)........8W-11-13
LCD Illumination Relay....................8W-11-17
Overhead Console.....................8W-11-10, 14
Powertrain Control Module..........8W-11-4, 5, 8, 9, 11
Power Distribution Center...................8W-11-2
Power Door Lock Relay...................8W-11-16
Power Door Unlock Relay..................8W-11-16
Radiator Fan Control Relay................8W-11-3, 11
Remote Keyless Entry Module.............8W-11-10, 12
Relay Center...........................8W-11-16
Telltale Connector (I.P. Cluster)..........8W-11-6, 10, 12
Torque Converter Clutch (TCC) Relay...........8W-11-15
Transmission Control Module...............8W-11-5, 8
J8W-11 POWER DISTRIBUTIONÐXJ VEHICLES 8W - 11 - 1

STARTING SYSTEM
INDEX
page page
Diagram Index............................ 1Starting System........................... 1
STARTING SYSTEM
AUTOMATIC TRANSMISSIONS
Circuit A0 from the battery is double crimped at
the positive battery post. One branch of circuit A0
(battery positive cable) connects to the engine starter
motor. The other A0 branch supplies voltage to the
bus bar in the power distribution center (PDC).
Fuse 7 in the PDC supplies battery voltage to the
contact side of the engine starter motor relay on cir-
cuit A4. When the coil side of the engine starter mo-
tor relay energizes, the contacts close and connect
circuit A4 to circuit T40. Circuit T40 supplies battery
voltage to the starter motor solenoid.
The ignition switch supplies battery voltage to the
coil side of the starter motor relay on circuit A41
when the key is moved to the START position and
the PARK/NEUTRAL position switch is closed.
Ground for the coil side of the starter motor relay is
supplied by the case grounded PARK/NEUTRAL po-
sition switch. Circuit T41 connects the coil side of the
relay to the PARK/NEUTRAL position switch.
When the starter motor relay energizes and the
contacts close, circuit T40 supplies battery voltage to
the starter motor solenoid. Circuit A0 from the bat-
tery supplies voltage to the starter motor when the
solenoid energizes.
MANUAL TRANSMISSIONS
Circuit A0 from the battery is double crimped at
the positive battery post. One branch of circuit A0
(battery positive cable) connects to the battery
starter motor. The other A0 branch supplies voltage
to the buss bar in the power distribution center
(PDC).
Fuse 7 in the PDC supplies battery voltage to the
contact side of the engine starter motor relay on cir-
cuit A4. When the coil side of the engine starter mo-
tor relay energizes, the contacts close and connect
circuit A4 to circuit T40. Circuit T40 supplies battery
voltage to the starter motor solenoid.The ignition switch supplies battery voltage to the
coil side of the starter motor relay on circuit A41
when the key is moved to the START position. Cir-
cuit Z12 provides ground for the coil side of the relay.
When the starter motor relay energizes and the
contacts close, circuit T40 supplies battery voltage to
the starter motor solenoid. Circuit A0 from the bat-
tery supplies voltage to the starter motor when the
solenoid energizes.
HELPFUL INFORMATION
²The Park/Neutral switch closes when the trans-
mission is in either the PARK or NEUTRAL posi-
tions.
²Circuit T41 also connects to cavity 30 of the pow-
ertrain control module (PCM). This input tells the
PCM the operator is starting the vehicle.
²Circuit A4 is double crimped at the contact side of
the starter motor relay. The A4 branch leaving the
relay powers fuse 13 in the PDC.
DIAGRAM INDEX
Component Page
Battery (2.5L)...........................8W-21-2
Battery (4.0L)...........................8W-21-3
Engine Starter Motor (2.5L)..................8W-21-2
Engine Starter Motor (4.0L)..................8W-21-3
Engine Starter Motor Relay (2.5L)..............8W-21-2
Engine Starter Motor Relay (4.0L)..............8W-21-3
Ignition Switch (2.5L)......................8W-21-2
Ignition Switch (4.0L)......................8W-21-3
PDC Fuse 6 (2.5L).......................8W-21-2
PDC Fuse 6 (4.0L).......................8W-21-3
PDC Fuse 7 (2.5L).......................8W-21-2
PDC Fuse 7 (4.0L).......................8W-21-3
Powertrain Control Module (2.5L)..............8W-21-2
Powertrain Control Module (4.0L)..............8W-21-3
Park/Neutral Position Switch (2.5L).............8W-21-2
Park/Neutral Position Switch (4.0L).............8W-21-3
J8W-21 STARTING SYSTEMÐXJ VEHICLES 8W - 21 - 1

The PCM provides a ground for the engine coolant
temperature sensor signal (circuit K2) through circuit
K4. Circuit K4 connects to cavity 4 of the PCM con-
nector.
HELPFUL INFORMATION
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
THROTTLE POSITION SENSOR
From the Powertrain Control Module (PCM), cir-
cuit K6 supplies 5 volts to the throttle position sen-
sor (TPS). Circuit K6 connects to cavity 6 of the
PCM.
Circuit K22 delivers the TPS signal to the PCM.
Circuit K22 connects to cavity 22 of the PCM.
The PCM provides a ground for the throttle posi-
tion sensor signal (circuit K22) through circuit K4.
Circuit K4 connects to cavity 4 of the PCM.
HELPFUL INFORMATION
Refer to Group 14 for throttle position sensor oper-
ation.
Circuit K6 splices to supply 5 volts to the manifold
absolute pressure sensor.
On vehicles equipped with the 4.0L engine and au-
tomatic transmission, circuit K22 splices to the
transmission control module.
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
MANIFOLD ABSOLUTE PRESSURE SENSOR
From the Powertrain Control Module (PCM), cir-
cuit K6 supplies 5 volts to the manifold absolute
pressure (MAP) sensor. Circuit K6 connects to cavity
6 of the PCM.
Circuit K1 delivers the MAP signal to the PCM.
Circuit K1 connects to cavity 1 of the PCM.
The PCM provides a ground for the MAP sensor
signal (circuit K1) through circuit K4. Circuit K4 con-
nects to cavity 4 of the PCM.
HELPFUL INFORMATION
Refer to Group 14 for MAP sensor operation.
Circuit K6 splices to supply 5 volts to the throttle
position sensor.
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
INTAKE AIR TEMPERATURE SENSOR
The intake air temperature sensor provides an in-
put to the Powertrain Control Module (PCM) on cir-
cuit K21. Circuit K21 connects to cavity 21 of the
PCM.
From circuit K21, the intake air temperature sen-
sor draws voltage from the PCM. The sensor is a
variable resistor. As intake air temperature changes,
the resistance in the sensor changes, causing a
change in current draw.
The PCM provides a ground for the intake air tem-
perature sensor signal (circuit K21) through circuit
K4. Circuit K4 connects to cavity 4 of the PCM.
HELPFUL INFORMATION
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
PARK/NEUTRAL POSITION SWITCH
When closed, the case-grounded park/neutral posi-
tion switch provides a ground path on circuit T41 for
the coil side of the starter motor relay. Circuit A41
from the ignition switch provides battery voltage to
the coil side of the relay.
Circuit T41 splices to cavity 30 of the PCM. The
park/neutral position switch provides an input to the
Powertrain Control Module (PCM).
TORQUE CONVERTER CLUTCH (TCC) SOLENOID
AND RELAY
The TCC solenoid is only used on 2.5L engines
with the three-speed automatic transmissions. The
Powertrain Control Module (PCM) operates the TCC
solenoid by energizing the TCC relay.
8W - 30 - 4 8W-30 FUEL/IGNITIONÐXJ VEHICLESJ

Circuit T17 from fuse 3 in the power distribution
center supplies voltage to the coil and contact sides
of the TCC relay. When the PCM provides a ground
path on circuit K54 for the coil side of the relay, the
relay contacts close.
When the relay contacts close, they connect circuit
T17 with circuit T22. Circuit T22 supplies battery
voltage to the case grounded TCC solenoid. Circuit
K54 connects to PCM cavity 54.
HELPFUL INFORMATION
²In the RUN or START position, the ignition switch
connects circuit A1 from fuse 4 in the PDC to circuit
A21.
UPSHIFT LAMP
On vehicles equipped with a manual transmission,
the PCM grounds the up-shift lamp on circuit K54.
Circuit K54 connects to cavity 54 of the PCM.
POWER STEERING PRESSURE SWITCH
The PCM supplies voltage to the power steering
pressure switch on circuit K10. Circuit Z12 provides
ground for the switch. When the switch closes, volt-
age flows through the switch to ground on circuit
Z12. The switch closes during periods of high power
steering pump load and low engine speed; such as
parking maneuvers.
Circuit K10 connects to cavity 10 of the PCM. Cir-
cuit Z12 terminates at the right rear of the engine.
TACHOMETER SIGNAL
The PCM supplies the signal for the tachometer on
circuit G21. Circuit G21 connects to cavity 43 of the
PCM.
MALFUNCTION INDICATOR LAMP (MIL)
The PCM provides ground for the instrument clus-
ter malfunction indicator lamp on circuit G3. The
MIL displays the message CHECK ENGINE when il-
luminated. Circuit F87 provides voltage for the lamp.
DATA LINK CONNECTOR
Circuit F12 supplies battery voltage to the data
link connector. Circuit F12 originates at fuse 11 in
the Power Distribution Center.
Circuit D20 connects to cavity 45 of the PCM. Cir-
cuit D20 is the SCI receive circuit for the PCM.
Circuit D21 connects to cavity 25 of the PCM. Cir-
cuit D21 is the SCI transmit circuit for the PCM.
Circuit Z11 provides ground for the data link con-
nector. Circuit Z11 terminates at the right rear of the
engine. Circuit Z11 also connects to cavity 5 of the
PCM.
HELPFUL INFORMATION
²Circuit Z1 also supplies a ground for the PCM
high current drivers.
²If the system loses ground for the Z11 circuits at
the right rear of the engine, the vehicle will not op-
erate. Check the connection at the ganged-ground cir-
cuit eyelet.
²Circuit F12 splices to supply battery voltage to the
vehicle speed control switch, back-up lamp switch,
A/C compressor clutch relay, windshield washer fluid
level sensor and radiator fan relay (4.0L engines).
BRAKE SWITCH INPUT
Circuit K29 provides the brake switch input to the
PCM. Circuit V40 connects to cavity 29 of the PCM.
POWER (DEVICE) GROUND
Circuit Z12 connects to cavities 11 and 12 of the
PCM. The Z12 circuit provides ground for PCM inter-
nal drivers that operate high current devices like the
injectors and ignition coil.
Internal to the PCM, the power (device) ground cir-
cuit connects to the PCM sensor return circuit (from
circuit K4).
HELPFUL INFORMATION
²The grounding point for circuit Z12 is the right
rear of the engine.
²If the system loses ground for the Z12 circuits at
the rear of the engine, the vehicle will not operate.
Check the connection at the ganged-ground circuit
eyelet.
²On vehicles equipped with the 4.0L engine and au-
tomatic transmission, circuit Z12 splices to provide
ground for the transmission control module.
EXTENDED IDLE SWITCH
On Police Package vehicles, an optional extended
idle switch provides an input to the Powertrain Con-
trol Module (PCM) on circuit K10. Circuit K10 con-
nects to cavity 10 of the PCM. Circuit F60 supplies
battery voltage to the extended idle switch. Circuit
Z1 grounds the switch.
CCD BUS
On vehicles equipped with the 4.0L engine, circuits
D1 and D2 connect the Powertrain Control Module
(PCM) to the CCD Bus. Circuit D1 connects to cavity
26 of the PCM. Circuit D2 connects to cavity 46 of
the PCM. Circuits D1 and D2 are a twisted pair of
wires.
J8W-30 FUEL/IGNITIONÐXJ VEHICLES 8W - 30 - 5

TRANSMISSION CONTROLS
UPSHIFT LAMP
On vehicles equipped with a manual transmission,
the PCM grounds the up-shift lamp on circuit K54.
Circuit K54 connects to cavity 54 of the PCM.
FOUR-WHEEL DRIVE (4WD) SWITCH
When the 4WD switch closes, circuit Z1 provides
ground for the 4WD indicator lamp in the instrument
cluster. Circuit F87 connects to the instrument clus-
ter and supplies battery voltage to the 4WD indicator
lamp. Circuit 107 connects the indicator lamp to the
4WD switch. Circuit 106 connects the lamp to the in-
strument cluster and circuit F87.
TRANSMISSION CONTROL MODULEÐ4.0L
ENGINE ONLY
Vehicles equipped with the 4.0L engine have elec-
tronically controlled solenoids in the automatic trans-
mission valve body.
The Transmission Control Module (TCM) receives
inputs from the Throttle Position Sensor (TPS) on
circuit K22 and the stop lamp switch on circuit K29.
Circuit K4 connects to the TCM to provide ground for
the TPS signal. The TCM receives the transmission
output speed sensor signal on circuit T505. Circuit
A14 from fuse 2 in the Power Distribution Center
supplies battery voltage to the TCM. Circuit Z12 pro-
vides ground for the TCM.
The TCM powers the S1 solenoid on circuit T510,
the S2 solenoid on circuit T509, and the S3 solenoid
on circuit T508. Circuit Z12 provides ground for the
S1, S2, and S3 solenoids.
TORQUE CONVERTER CLUTCH (TCC) SOLENOID
AND RELAYÐ2.5L ENGINE ONLY
The TCC solenoid is only used on 2.5L engines
with the three-speed automatic transmissions. The
Powertrain Control Module (PCM) operates the TCC
solenoid by energizing the TCC relay.
Circuit T17 from fuse 12 in the Power Distribution
Center (PDC) supplies voltage to the coil and contact
sides of the TCC relay. When the PCM provides a
ground path on circuit K54 for the coil side of the re-
lay, the relay contacts close.
When the relay contacts close, they connect circuit
T17 with circuit T22. Circuit T22 supplies battery
voltage to the case grounded TCC solenoid. Circuit
K54 connects to PCM cavity 54.
HELPFUL INFORMATION
²In the RUN or START position, the ignition switch
connects circuit A1 from fuse 6 in the PDC to circuit
A21.
DIAGRAM INDEX
Component Page
4-WD Indicator Lamp......................8W-31-4
4-WD Indicator Switch.....................8W-31-4
Back-Up Lamp Switch.....................8W-31-3
Fuse 2 (PDC)...........................8W-31-4
Fuse 6 (PDC).........................8W-31-2, 3
Fuse 11 (PDC)..........................8W-31-3
Fuse 12 (PDC)..........................8W-31-2
Ignition Switch........................8W-31-2, 3
Powertrain Control Module..................8W-31-2
Park/Neutral Position Switch.................8W-31-3
TCC Relay.............................8W-31-2
TCC Solenoid...........................8W-31-2
Transmission Control Module.................8W-31-2
J8W-31 TRANSMISSION CONTROLSÐXJ VEHICLES 8W - 31 - 1