Information JEEP GRAND CHEROKEE 2003 WJ / 2.G Workshop Manual

STANDARD PROCEDURE - TESTING OF
VOLTAGE POTENTIAL
(1) Connect the ground lead of a voltmeter to a
known good ground (Fig. 7).
(2) Connect the other lead of the voltmeter to the
selected test point. The vehicle ignition may need to
be turned ON to check voltage. Refer to the appropri-
ate test procedure.
STANDARD PROCEDURE - TESTING FOR
CONTINUITY
(1) Remove the fuse for the circuit being checked
or, disconnect the battery.
(2) Connect one lead of the ohmmeter to one side
of the circuit being tested (Fig. 8).
(3) Connect the other lead to the other end of the
circuit being tested. Low or no resistance means good
continuity.
STANDARD PROCEDURE - TESTING FOR A
SHORT TO GROUND
(1) Remove the fuse and disconnect all items
involved with the fuse.
(2) Connect a test light or a voltmeter across the
terminals of the fuse.
(3) Starting at the fuse block, wiggle the wiring
harness about six to eight inches apart and watch
the voltmeter/test lamp.
(4) If the voltmeter registers voltage or the test
lamp glows, there is a short to ground in that gen-
eral area of the wiring harness.
Fig. 7 TESTING FOR VOLTAGE POTENTIAL
Fig. 8 TESTING FOR CONTINUITY
1 - FUSE REMOVED FROM CIRCUIT
WJ8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 9
WIRING DIAGRAM INFORMATION (Continued)

STANDARD PROCEDURE - TESTING FOR A
SHORT TO GROUND ON FUSES POWERING
SEVERAL LOADS
(1) Refer to the wiring diagrams and disconnect or
isolate all items on the suspected fused circuits.
(2) Replace the blown fuse.
(3) Supply power to the fuse by turning ON the
ignition switch or re-connecting the battery.
(4) Start connecting or energizing the items in the
fuse circuit one at a time. When the fuse blows the
circuit with the short to ground has been isolated.
STANDARD PROCEDURE - TESTING FOR A
VOLTAGE DROP
(1) Connect the positive lead of the voltmeter to
the side of the circuit closest to the battery (Fig. 9).
(2) Connect the other lead of the voltmeter to the
other side of the switch, component or circuit.
(3) Operate the item.
(4) The voltmeter will show the difference in volt-
age between the two points.
SPECIAL TOOLS
WIRING/TERMINAL
Fig. 9 TESTING FOR VOLTAGE DROP
PROBING TOOL PACKAGE 6807
TERMINAL PICK TOOL SET 6680
TERMINAL REMOVING TOOLS 6932 AND 8638
TERMINAL REMOVING TOOL 6934
8W - 01 - 10 8W-01 WIRING DIAGRAM INFORMATIONWJ
WIRING DIAGRAM INFORMATION (Continued)

CONNECTOR
REMOVAL
(1) Disconnect battery.
(2) Release Connector Lock (Fig. 10).
(3) Disconnect the connector being repaired from
its mating half/component.
(4) Remove the dress cover (if applicable) (Fig. 10).
(5) Release the Secondary Terminal Lock, if
required (Fig. 11).
(6) Position the connector locking finger away from
the terminal using the proper special tool. Pull on
the wire to remove the terminal from the connector
(Fig. 12).
INSTALLATION
(1) Insert the removed terminal in the same cavity
on the repair connector.
(2) Repeat steps for each terminal in the connec-
tor, being sure that all wires are inserted into the
proper cavities. For additional connector pin-out
identification, refer to the wiring diagrams.
(3) When the connector is re-assembled, the sec-
ondary terminal lock must be placed in the locked
position to prevent terminal push out.
(4) Replace dress cover (if applicable).
(5) Connect connector to its mating half/compo-
nent.
(6) Connect battery and test all affected systems.
Fig. 10 REMOVAL OF DRESS COVER
1 - DRESS COVER
2 - CONNECTOR LOCK
3 - CONNECTOR
WJ8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 11

Fig. 11 EXAMPLES OF CONNECTOR SECONDARY TERMINAL LOCKS
1 - Secondary Terminal Lock
8W - 01 - 12 8W-01 WIRING DIAGRAM INFORMATIONWJ
CONNECTOR (Continued)

Fig. 12 TERMINAL REMOVAL
1 - TYPICAL CONNECTOR
2 - PICK FROM SPECIAL TOOL KIT 6680
3 - APEX CONNECTOR
4 - PICK FROM SPECIAL TOOL KIT 6680
5 - AUGAT CONNECTOR
6 - SPECIAL TOOL 6932
7 - MOLEX CONNECTOR8 - SPECIAL TOOL 6742
9 - THOMAS AND BETTS CONNECTOR
10 - SPECIAL TOOL 6934
11 - TYCO CONNECTOR
12 - SPECIAL TOOL 8638
WJ8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 13
CONNECTOR (Continued)

DIODE
REMOVAL
(1) Disconnect the battery.
(2) Locate the diode in the harness, and remove
the protective covering.
(3) Remove the diode from the harness, pay atten-
tion to the current flow direction (Fig. 13).
INSTALLATION
(1) Remove the insulation from the wires in the
harness. Only remove enough insulation to solder in
the new diode.
(2) Install the new diode in the harness, making
sure current flow is correct. If necessary, refer to the
appropriate wiring diagram for current flow (Fig. 13).
(3) Solder the connection together using rosin core
type solder only.Do not use acid core solder.
(4) Tape the diode to the harness using electrical
tape. Make sure the diode is completely sealed from
the elements.
(5) Re-connect the battery and test affected sys-
tems.
TERMINAL
REMOVAL
(1) Follow steps for removing terminals described
in the connector removal section.
(2) Cut the wire 6 inches from the back of the con-
nector.
INSTALLATION
(1) Select a wire from the terminal repair kit that
best matches the color and gage of the wire being
repaired.
(2) Cut the repair wire to the proper length and
remove one±half (1/2) inch of insulation.
(3) Splice the repair wire to the wire harness (see
wire splicing procedure).
(4) Insert the repaired wire into the connector.
(5) Install the connector locking wedge, if required,
and reconnect the connector to its mating half/compo-
nent.
(6) Re-tape the wire harness starting at 1±1/2
inches behind the connector and 2 inches past the
repair.
(7) Connect battery and test all affected systems.
Fig. 13 DIODE IDENTIFICATION
1 - CURRENT FLOW
2 - BAND AROUND DIODE INDICATES CURRENT FLOW
3 - DIODE AS SHOWN IN THE DIAGRAMS
8W - 01 - 14 8W-01 WIRING DIAGRAM INFORMATIONWJ

WIRE
STANDARD PROCEDURE - WIRE SPLICING
When splicing a wire, it is important that the cor-
rect gage be used as shown in the wiring diagrams.
(1) Remove one-half (1/2) inch of insulation from
each wire that needs to be spliced.
(2) Place a piece of adhesive lined heat shrink tub-
ing on one side of the wire. Make sure the tubing will
be long enough to cover and seal the entire repair
area.
(3) Place the strands of wire overlapping each
other inside of the splice clip (Fig. 14).
(4) Using crimping tool, Mopar p/n 05019912AA,
crimp the splice clip and wires together (Fig. 15).(5) Solder the connection together using rosin core
type solder only (Fig. 16).
CAUTION: DO NOT USE ACID CORE SOLDER.
(6) Center the heat shrink tubing over the joint
and heat using a heat gun. Heat the joint until the
tubing is tightly sealed and sealant comes out of both
ends of the tubing (Fig. 17).
Fig. 14 SPLICE BAND
1 - SPLICE BAND
Fig. 15 CRIMPING TOOL
1 - CRIMPING TOOL
Fig. 16 SOLDER SPLICE
1 - SOLDER
2 - SPLICE BAND
3 - SOLDERING IRON
Fig. 17 HEAT SHRINK TUBE
1 - SEALANT
2 - HEAT SHRINK TUBE
WJ8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 15

Component Page
Power Outlet......................... 8W-41
Power Seats.......................... 8W-63
Power Windows....................... 8W-60
Powertrain Control Module.............. 8W-30
Radio............................... 8W-47
Rain Sensor.......................... 8W-49
Recirculation Door Motor/Actuator........ 8W-42
Red Brake Warning Indicator Switch....... 8W-35
Remote Keyless Module................. 8W-39
Remote Radio Switches................. 8W-47
Splices.............................. 8W-10
Seat Belt Switch...................... 8W-43
Seat Module.......................... 8W-63
Sentry Key Immobilizer Module.......... 8W-39
Shifter Assembly...................... 8W-31
Side Impact Sensors................... 8W-43
Side Marker Lamps.................... 8W-50
Side Repeater Lamps................... 8W-52
Siren............................... 8W-49
Speakers............................ 8W-47Component Page
Speed Control Switches................. 8W-33
Sunroof............................. 8W-64
Temperature Valve Actuator............. 8W-42
Throttle Position Sensor................ 8W-30
Trailer Tow.......................... 8W-54
Transfer Case Position Sensor............ 8W-31
Transmission......................... 8W-31
Turn Signal Lamps.................... 8W-52
Underhood Lamp...................... 8W-44
Vehicle Information Center.............. 8W-49
Viscous/Cabin Heater................... 8W-30
Visor/Vanity Lamps.................... 8W-44
Washer Fluid Level Switch.............. 8W-53
Wastegate Solenoid.................... 8W-30
Water In Fuel Sensor................... 8W-30
Wheel Speed Sensors................... 8W-35
Window Defogger...................... 8W-48
Wiper High/Low Relay.................. 8W-53
Wiper Motor.......................... 8W-53
Washer Pump......................... 8W-5
8W - 02 - 2 8W-02 COMPONENT INDEXWJ

8W-12 JUNCTION BLOCK
Component PageA/C Compressor Clutch Relay................8W-12-18
Accessory Delay Relay.....................8W-12-25
Adjustable Pedals Module..................8W-12-11
Airbag Control Module....................8W-12-25
Auto Shut Down Relay....................8W-12-18
Automatic Day/Night Mirror.................8W-12-23
Automatic Headlamp Light Sensor/VTSS LED......8W-12-15
Automatic Zone Control Module..........8W-12-15, 17, 22
Back-Up Lamp Relay.....................8W-12-22
Body Control Module . . . 8W-12-10, 12, 13, 15, 17, 20, 23, 24, 25,
26, 27, 28, 29, 30, 31, 35, 36
Brake Lamp Switch......................8W-12-24
Cargo Lamp......................8W-12-16, 24, 27
Cigar Lighter..........................8W-12-17
Cigar Lighter Relay....................8W-12-17, 26
Circuit Breaker No. 1...................8W-12-28, 29
Circuit Breaker No. 2......................8W-12-9
Clockspring...........................8W-12-31
Combination Flasher............8W-12-10, 22, 27, 32, 35
Controller Antilock Brake..................8W-12-21
Data Link Connector.....................8W-12-10
Driver Door Module......................8W-12-34
Driver Heated Seat Switch..................8W-12-22
Driver Lumbar Switch.....................8W-12-9
Driver Power Seat Switch...................8W-12-9
Electric Brake..........................8W-12-21
Engine Control Module....................8W-12-19
Engine Starter Motor Relay.................8W-12-26
EVAP/Purge Solenoid.....................8W-12-18
Fog Lamp Relay........................8W-12-24
Front Power Outlet......................8W-12-11
Front Wiper Motor....................8W-12-28, 29
Fuel Pump Relay........................8W-12-18
Fuse 2..............................8W-12-17
Fuse 3............................8W-12-10, 20
Fuse 4..............................8W-12-10
Fuse 5..............................8W-12-11
Fuse 6............................8W-12-12, 13
Fuse 7..............................8W-12-15
Fuse 8..............................8W-12-16
Fuse 9..............................8W-12-11
Fuse 10..............................8W-12-11
Fuse 11..............................8W-12-17
Fuse 12.......................8W-12-18, 19, 21, 34
Fuse 14..............................8W-12-20
Fuse 15.........................8W-12-11, 15, 20
Fuse 16..............................8W-12-10
Fuse 17..............................8W-12-10
Fuse 18...........................8W-12-21, 34
Fuse 19..............................8W-12-21
Fuse 20..............................8W-12-22
Fuse 21...........................8W-12-18, 19
Fuse 22..............................8W-12-23
Fuse 23..............................8W-12-24
Fuse 24..............................8W-12-24
Fuse 25..............................8W-12-25
Fuse 26..............................8W-12-17
Fuse 27..............................8W-12-36
Fuse 28..............................8W-12-26
Fuse 29..............................8W-12-26
Fuse 30..............................8W-12-26
Fuse 31..............................8W-12-26
Fuse 32..............................8W-12-25
Fuse 33..............................8W-12-25
G200...............................8W-12-35
Glove Box Lamp........................8W-12-16
Headlamp Leveling Switch...............8W-12-12, 13
High Beam Relay........................8W-12-10
Horn Relay...........................8W-12-31
Horn Switch...........................8W-12-31
Instrument Cluster..................8W-12-10, 23, 32
Intrusion Transceiver Module................8W-12-16
Junction Block.........8W-12-2, 3, 9, 10, 11, 12, 13, 15, 16,
17, 18, 19, 20, 21, 22, 23, 24, 25,
26, 27, 28, 29, 30, 31, 32, 34, 35, 36Component PageLeft Courtesy Lamp......................8W-12-16
Left Door Handle Courtesy Lamp.........8W-12-16, 24, 30
Left Fog Lamp.........................8W-12-24
Left Front Park Lamp.....................8W-12-14
Left Front Park/Turn Signal Lamp...........8W-12-14, 33
Left Front Side Marker Lamp..............8W-12-14, 33
Left Front Turn Signal Lamp................8W-12-33
Left Headlamp Leveling Motor...............8W-12-14
Left High Beam Headlamp..................8W-12-10
Left Liftgate Ajar Switch...................8W-12-30
Left Low Beam Headlamp..................8W-12-20
Left Multi-Function Switch...............8W-12-10, 35
Left Rear Door Lock Motor/Ajar Switch..........8W-12-27
Left Rear Lamp Assembly...........8W-12-12, 13, 27, 36
Left Side Repeater Lamp...................8W-12-32
Left Visor/Vanity Lamp..................8W-12-16, 30
License Lamp No. 1....................8W-12-12, 13
License Lamp No. 2....................8W-12-12, 13
Liftgate Flip-Up Ajar Switch.................8W-12-30
Liftgate Flip-Up Push Button Switch...........8W-12-16
Liftgate Power Lock Motor..................8W-12-16
Low Beam Relay........................8W-12-20
Low Beam/Daytime Running Lamp Relay.........8W-12-20
Manual Temperature Control..............8W-12-17, 22
Overhead Map/Courtesy Lamp...........8W-12-16, 24, 30
Park Lamp Relay.....................8W-12-12, 13
Park/Neutral Position Switch................8W-12-22
Passenger Door Module....................8W-12-34
Passenger Heated Seat Switch...............8W-12-22
Passenger Lumbar Switch...................8W-12-9
Passenger Power Seat Switch.................8W-12-9
Power Amplifier.........................8W-12-11
Power Connector........................8W-12-11
Power Distribution Center....8W-12-10, 11, 15, 17, 20, 21, 34
Powertrain Control Module.................8W-12-18
Radio.............................8W-12-11, 26
Rain Sensor...........................8W-12-25
Rear Window Defogger....................8W-12-17
Rear Window Defogger Relay................8W-12-17
Rear Wiper Motor.....................8W-12-16, 30
Remote Keyless Module....................8W-12-15
Right Courtesy Lamp.....................8W-12-16
Right Door Handle Courtesy Lamp........8W-12-16, 24, 30
Right Fog Lamp........................8W-12-24
Right Front Park Lamp....................8W-12-14
Right Front Park/Turn Signal Lamp..........8W-12-14, 33
Right Front Side Marker Lamp.............8W-12-14, 33
Right Front Turn Signal Lamp...............8W-12-33
Right Headlamp Leveling Motor..............8W-12-14
Right High Beam Headlamp.................8W-12-10
Right Liftgate Ajar Switch..................8W-12-30
Right Low Beam Headlamp.................8W-12-20
Right Multi-Function Switch.................8W-12-26
Right Rear Lamp Assembly..........8W-12-12, 13, 32, 36
Right Side Repeater Lamp..................8W-12-32
Right Visor/Vanity Lamp.................8W-12-16, 30
Seat Module...........................8W-12-9
Sentry Key Immobilizer Module............8W-12-15, 23
Shifter Assembly......................8W-12-18, 19
Siren...............................8W-12-15
Sunroof Control Module....................8W-12-25
Temperature Valve Actuator.................8W-12-22
Trailer Tow Brake Lamp Relay...............8W-12-21
Trailer Tow Circuit Breaker.................8W-12-17
Trailer Tow Connector.....................8W-12-12
Trailer Tow Left Turn Relay.................8W-12-27
Trailer Tow Right Turn Relay................8W-12-32
Transmission Control Module..............8W-12-18, 26
Transmission Solenoid/TRS Assembly...........8W-12-22
Underhood Lamp........................8W-12-15
Vehicle Information Center...............8W-12-16, 23
Wiper High/Low Relay..................8W-12-28, 29
Wiper On/Off Relay....................8W-12-28, 29
WJ8W-12 JUNCTION BLOCK 8W - 12 - 1

8W-15 GROUND DISTRIBUTION
Component Page
A/C Compressor Clutch.................. 8W-15-4
Adjustable Pedals Module............. 8W-15-17, 21
Airbag Control Module.................. 8W-15-16
Ash Receiver Lamp.................... 8W-15-14
Automatic Day/Night Mirror.............. 8W-15-19
Automatic Zone Control Module........... 8W-15-15
Battery............................ 8W-15-2, 3
Blower Motor Controller................. 8W-15-15
Body Control Module.............. 8W-15-12, 13, 15
Brake Lamp Switch................. 8W-15-17, 22
Center High Mounted Stop Lamp.......... 8W-15-20
Cigar Lighter........................ 8W-15-14
Cigar Lighter Relay.................... 8W-15-12
Controller Antilock Brake................ 8W-15-12
Coolant Level Sensor............... 8W-15-9, 10, 11
Crankcase Heater...................... 8W-15-4
Data Link Connector.................. 8W-15-2, 3
Driver Cylinder Lock Switch.............. 8W-15-16
Driver Door Lock Motor/Ajar Switch........ 8W-15-16
Driver Door Module.................... 8W-15-16
Driver Heated Seat Switch............... 8W-15-14
Driver Lumbar Switch............... 8W-15-18, 21
Driver Power Seat Switch............. 8W-15-18, 21
Driver Rear Power Window Switch....... 8W-15-18, 21
Electric Brake........................ 8W-15-17
Electronic Speed Control Servo.......... 8W-15-9, 10
Engine Control Module.................. 8W-15-3
Front Power Outlet.................... 8W-15-14
Front Washer Pump................... 8W-15-6, 7
Front Wiper Motor.................... 8W-15-6, 7
Fuel Pump Module.................... 8W-15-19
G100............................. 8W-15-2, 3
G101............................. 8W-15-2, 3
G102............................... 8W-15-2
G103............................. 8W-15-2, 3
G104............................... 8W-15-4
G105............................... 8W-15-4
G106............................. 8W-15-6, 7
G107.............................. 8W-15-12
G108.......................... 8W-15-9, 10, 11
G200......................... 8W-15-13, 14, 15
G201.............................. 8W-15-16
G300......................... 8W-15-16, 17, 18
G301......................... 8W-15-19, 21, 22
Headlamp Leveling Switch............... 8W-15-15
Hood Ajar Switch..................... 8W-15-6, 7
Horn No. 1...................... 8W-15-9, 10, 11
Horn No. 2...................... 8W-15-9, 10, 11
Hydraulic Cooling Module........... 8W-15-9, 10, 11
Ignition Switch....................... 8W-15-15
Instrument Cluster.................. 8W-15-13, 14
Intake Port Swirl Actuator................ 8W-15-3
Intrusion Transceiver Module.......... 8W-15-21, 22
Junction Block.................. 8W-15-12, 13, 15
Left Fog Lamp...................... 8W-15-6, 7
Left Front Park Lamp................... 8W-15-5
Left Front Park/Turn Signal Lamp.......... 8W-15-5
Left Front Turn Signal Lamp.............. 8W-15-5
Left Headlamp Leveling Motor............. 8W-15-5
Left High Beam Headlamp................ 8W-15-5
Component Page
Left Liftgate Ajar Switch................ 8W-15-20
Left Low Beam Headlamp................ 8W-15-5
Left Multi-Function Switch............... 8W-15-15
Left Rear Door Lock Motor/Ajar Switch.... 8W-15-21, 22
Left Rear Lamp Assembly............... 8W-15-19
Left Side Repeater Lamp............... 8W-15-6, 7
License Lamp No. 1.................... 8W-15-20
License Lamp No. 2.................... 8W-15-20
Liftgate Flip-Up Ajar Switch.............. 8W-15-20
Liftgate Flip-Up Release Solenoid.......... 8W-15-20
Line Pressure Sensor.................... 8W-15-2
Low Beam/Daytime Running Lamp Relay.... 8W-15-12
Manual Temperature Control........... 8W-15-13, 15
Oxygen Sensor 1/2 Downstream............ 8W-15-4
Oxygen Sensor 2/2 Downstream............ 8W-15-4
Park Lamp Relay..................... 8W-15-12
Passenger Door Lock Motor/Ajar Switch...... 8W-15-16
Passenger Door Module................. 8W-15-16
Passenger Heated Seat Switch............ 8W-15-14
Passenger Lumbar Switch............. 8W-15-17, 22
Passenger Power Seat Switch.......... 8W-15-17, 22
Passenger Rear Power Window Switch.... 8W-15-16, 22
Power Amplifier.................... 8W-15-17, 18
Power Connector...................... 8W-15-15
Powertrain Control Module............... 8W-15-2
Radio........................... 8W-15-17, 18
Rain Sensor....................... 8W-15-21, 22
Rear Power Outlet.................. 8W-15-17, 18
Rear Washer Pump................... 8W-15-6, 7
Rear Window Defogger.................. 8W-15-20
Rear Wiper Motor..................... 8W-15-20
Remote Keyless Module................. 8W-15-16
Right Fog Lamp.................. 8W-15-9, 10, 11
Right Front Park Lamp.................. 8W-15-8
Right Front Park/Turn Signal Lamp......... 8W-15-8
Right Front Turn Signal Lamp............. 8W-15-8
Right Headlamp Leveling Motor............ 8W-15-8
Right High Beam Headlamp............... 8W-15-8
Right Low Beam Headlamp............... 8W-15-8
Right Rear Door Lock Motor/Ajar Switch . . 8W-15-16, 18
Right Rear Lamp Assembly............ 8W-15-17, 18
Right Side Repeater Lamp........... 8W-15-9, 10, 11
Seat Module...................... 8W-15-18, 21
Sentry Key Immobilizer Module........... 8W-15-13
Shifter Assembly................... 8W-15-14, 15
Siren............................. 8W-15-6, 7
Sunroof Control Module................. 8W-15-19
Sunroof Motor........................ 8W-15-19
Sunroof Switch....................... 8W-15-19
Temperature Valve Actuator.............. 8W-15-13
Trailer Tow Brake Lamp Relay............ 8W-15-19
Trailer Tow Connector.................. 8W-15-19
Trailer Tow Left Turn Relay.............. 8W-15-19
Trailer Tow Right Turn Relay............. 8W-15-19
Transmission Control Module.............. 8W-15-2
Transmission Control Relay............ 8W-15-9, 10
Underhood Lamp..................... 8W-15-6, 7
Vehicle Information Center............ 8W-15-21, 22
Viscous/Cabin Heater................... 8W-15-4
Washer Fluid Level Switch.............. 8W-15-6, 7
WJ8W-15 GROUND DISTRIBUTION 8W - 15 - 1