power distribution JEEP GRAND CHEROKEE 2003 WJ / 2.G Repair Manual

8W-31 TRANSMISSION CONTROL SYSTEM
Component Page
Auto Shut Down Relay................ 8W-31-4
Back-Up Lamp Relay................ 8W-31-15
Body Control Module................ 8W-31-14
Brake Lamp Switch............... 8W-31-14, 15
Controller Antilock Brake............. 8W-31-17
Crankshaft Position Sensor.......... 8W-31-9, 10
Data Link Connector............ 8W-31-9, 10, 16
Diagnostic Junction Port............ 8W-31-4, 15
Engine Control Module............ 8W-31-16, 17
Engine Starter Motor Relay..... 8W-31-4, 5, 6, 12
Fuel Pump Relay.................... 8W-31-4
Fuse 5........................... 8W-31-2, 3
Fuse 12......................... 8W-31-4, 15
Fuse 20.......................... 8W-31-5, 6
Fuse 21........................ 8W-31-14, 15
Fuse 28.......................... 8W-31-2, 8
Fuse 31............................ 8W-31-4
G102.......................... 8W-31-11, 13
G108.............................. 8W-31-3
G200.......................... 8W-31-14, 15
G300............................. 8W-31-15
G301............................. 8W-31-15Component Page
Generator.......................... 8W-31-2
Input Speed Sensor.................. 8W-31-13
Junction Block............. 8W-31-4, 5, 6, 14, 15
Left Rear Lamp Assembly............ 8W-31-5, 6
Line Pressure Sensor................ 8W-31-13
Output Speed Sensor.............. 8W-31-8, 13
Park/Neutral Position Switch........... 8W-31-6
Power Distribution Center......... 8W-31-2, 3, 8
Powertrain Control
Module......... 8W-31-2, 4, 5, 6, 7, 8, 9, 10, 14
Right Rear Lamp Assembly........... 8W-31-5, 6
Shifter Assembly.............. 8W-31-14, 15, 16
Throttle Position Sensor............... 8W-31-7
Transfer Case Position Sensor........ 8W-31-6, 16
Transmission Control
Module........... 8W-31-3, 4, 7, 9, 10, 11, 12,
13, 14, 16, 17, 18
Transmission Control Relay . . . 8W-31-2, 3, 8, 11, 12
Transmission Solenoid.............. 8W-31-2, 8
Transmission Solenoid Assembly........ 8W-31-18
Transmission Solenoid/TRS
Assembly.............. 8W-31-3, 5, 11, 12, 13
WJ8W-31 TRANSMISSION CONTROL SYSTEM 8W - 31 - 1

8W-35 ANTILOCK BRAKES
Component Page
Brake Lamp Switch.................. 8W-35-5
Controller Antilock Brake...... 8W-35-2, 3, 4, 5, 6
Diagnostic Junction Port............. 8W-35-2, 3
Engine Control Module.............. 8W-35-4, 5
Fuse 4........................... 8W-35-2, 3
Fuse 19.......................... 8W-35-2, 3
Fuse 23............................ 8W-35-5
Fuse 25.......................... 8W-35-2, 3
G107............................ 8W-35-2, 3Component Page
Junction Block.................. 8W-35-2, 3, 5
Left Front Wheel Speed Sensor......... 8W-35-6
Left Rear Wheel Speed Sensor.......... 8W-35-6
Power Distribution Center........... 8W-35-2, 3
Powertrain Control Module............. 8W-35-4
Red Brake Warning Indicator Switch..... 8W-35-5
Right Front Wheel Speed Sensor........ 8W-35-6
Right Rear Wheel Speed Sensor......... 8W-35-6
WJ8W-35 ANTILOCK BRAKES 8W - 35 - 1

8W-39 VEHICLE THEFT SECURITY SYSTEM
Component Page
Automatic Headlamp Light
Sensor/VTSS LED.................. 8W-39-3
Body Control Module . . . 8W-39-2, 3, 4, 5, 7, 8, 9, 10
Clockspring....................... 8W-39-7, 8
Diagnostic Junction Port............... 8W-39-9
Driver Cylinder Lock Switch............ 8W-39-6
Driver Door Lock Motor/Ajar Switch...... 8W-39-6
Driver Door Module................ 8W-39-6, 11
Engine Starter Motor Relay............ 8W-39-2
Fuse 7........................ 8W-39-3, 9, 11
Fuse 8............................. 8W-39-2
Fuse 18.......................... 8W-39-7, 8
Fuse 22.......................... 8W-39-2, 9
Fuse 28............................ 8W-39-2
G106............................. 8W-39-10
G108............................ 8W-39-7, 8
G200.............................. 8W-39-9
G300............................ 8W-39-5, 6Component Page
G301....................... 8W-39-4, 5, 6, 11
Hood Ajar Switch................... 8W-39-10
Horn No. 1....................... 8W-39-7, 8
Horn No. 2....................... 8W-39-7, 8
Horn Relay....................... 8W-39-7, 8
Horn Switch...................... 8W-39-7, 8
Ignition Switch...................... 8W-39-2
Junction Block........ 8W-39-2, 3, 4, 5, 7, 8, 9, 11
Left Liftgate Ajar Switch.............. 8W-39-4
Left Rear Door Lock Motor/Ajar Switch . . . 8W-39-5
Liftgate Flip-Up Ajar Switch............ 8W-39-4
Passenger Door Lock Motor/Ajar Switch . . . 8W-39-6
Passenger Door Module............... 8W-39-6
Power Distribution Center......... 8W-39-2, 7, 8
Remote Keyless Module.............. 8W-39-11
Right Liftgate Ajar Switch............. 8W-39-4
Right Rear Door Lock Motor/Ajar Switch . . 8W-39-5
Sentry Key Immobilizer Module......... 8W-39-9
WJ8W-39 VEHICLE THEFT SECURITY SYSTEM 8W - 39 - 1

8W-41 HORN/CIGAR LIGHTER/POWER OUTLET
Component Page
Body Control Module............... 8W-41-2, 3
Cigar Lighter....................... 8W-41-4
Cigar Lighter Relay.................. 8W-41-4
Circuit Breaker...................... 8W-41-4
Clockspring....................... 8W-41-2, 3
Front Power Outlet................... 8W-41-5
Fuse 9............................. 8W-41-5
Fuse 18.......................... 8W-41-2, 3
Fuse 26............................ 8W-41-4
Fuse 27............................ 8W-41-5
Fuse 29............................ 8W-41-4
G108............................ 8W-41-2, 3Component Page
G200............................ 8W-41-4, 5
G300.............................. 8W-41-5
Horn No. 1....................... 8W-41-2, 3
Horn No. 2....................... 8W-41-2, 3
Horn Relay....................... 8W-41-2, 3
Horn Switch...................... 8W-41-2, 3
Junction Block................ 8W-41-2, 3, 4, 5
Power Connector..................... 8W-41-5
Power Distribution Center......... 8W-41-2, 3, 5
Rear Power Outlet................... 8W-41-5
Trailer Tow Circuit Breaker............ 8W-41-4
WJ8W-41 HORN/CIGAR LIGHTER/POWER OUTLET 8W - 41 - 1

8W-42 AIR CONDITIONING-HEATER
Component Page
A/C Compressor Clutch.............. 8W-42-3, 4
A/C Compressor Clutch Relay......... 8W-42-3, 4
A/C Pressure Transducer........ 8W-42-11, 12, 13
Auto Shut Down Relay.......... 8W-42-4, 11, 12
Automatic Zone Control Module . 8W-42-2, 5, 6, 7, 8
Blower Motor................... 8W-42-2, 6, 9
Blower Motor Controller............. 8W-42-2, 6
Blower Motor Resistor Block............ 8W-42-9
Body Control Module........... 8W-42-5, 6, 9, 10
Diagnostic Junction Port............... 8W-42-5
Driver Blend Door Motor/Actuator..... 8W-42-7, 8
Engine Control Module............. 8W-42-4, 13
Fuse 1......................... 8W-42-2, 6, 9
Fuse 7............................. 8W-42-6
Fuse 11......................... 8W-42-5, 10
Fuse 16...................... 8W-42-4, 11, 12
Fuse 20......................... 8W-42-2, 10
Fuse 21.......................... 8W-42-3, 4Component Page
G104.............................. 8W-42-3
G108.......................... 8W-42-11, 12
G200......................... 8W-42-2, 6, 10
Glow Plug Relay No. 1................ 8W-42-4
Hydraulic Cooling Module.......... 8W-42-11, 12
Junction Block.............. 8W-42-2, 3, 5, 6, 10
Manual Temperature Control...... 8W-42-2, 9, 10
Mode Door Motor/Actuator........... 8W-42-7, 8
Oxygen Sensor Downstream Relay . . . 8W-42-11, 12
Passenger Blend Door Motor/Actuator . . 8W-42-7, 8
Power Distribution
Center............. 8W-42-2, 3, 4, 6, 9, 11, 12
Powertrain Control Module....... 8W-42-3, 11, 12
Rear Window Defogger............. 8W-42-5, 10
Rear Window Defogger Relay........ 8W-42-5, 10
Recirculation Door Motor/Actuator..... 8W-42-7, 8
Temperature Valve Actuator........... 8W-42-10
Viscous/Cabin Heater Relay............ 8W-42-4
WJ8W-42 AIR CONDITIONING-HEATER 8W - 42 - 1

8W-60 POWER WINDOWS
Component Page
Body Control Module............... 8W-60-2, 3
Diagnostic Junction Port............. 8W-60-2, 3
Driver Door Module............ 8W-60-2, 3, 4, 5
Driver Front Power Window Motor..... 8W-60-2, 3
Driver Rear Power Window Motor....... 8W-60-5
Driver Rear Power Window Switch....... 8W-60-5
Fuse 12.......................... 8W-60-2, 3
G300........................ 8W-60-2, 4, 5, 6Component Page
G301........................ 8W-60-3, 4, 5, 6
Junction Block.................. 8W-60-2, 3, 4
Passenger Door Module.......... 8W-60-2, 3, 4, 6
Passenger Front Power
Window Motor................... 8W-60-2, 3
Passenger Rear Power Window Motor.... 8W-60-6
Passenger Rear Power Window Switch.... 8W-60-6
Power Distribution Center........... 8W-60-2, 3
WJ8W-60 POWER WINDOWS 8W - 60 - 1

CONNECTOR NAME/
NUMBERCOLOR LOCATION FIG.
Trailer Tow Brake Lamp Relay BK Left Quarter Panel N/S
Trailer Tow Circuit Breaker BK Left Quarter Panel N/S
Trailer Tow Connector BK In Rear Bumper 39
Trailer Tow Left Turn Relay BK Left Quarter Panel N/S
Trailer Tow Right Turn Relay BK Left Quarter Panel N/S
Transfer Case Position Sensor BK On Transfer Case 7
Transmission Control Module
(4.7L)BK Rear of Engine Compartment 14, 15, 18
Transmission Control Module
C1 (Diesel)BK Right Rear Side of Engine
CompartmentN/S
Transmission Control Module
C2 (Diesel)BK Right Rear Side of Engine
Compartment8
Transmission Solenoid (4.0L
Gas)BK Left Side of Transmission 12
Transmission Solenoid
Assembly (Diesel)BK On Transmission 8
Transmission Solenoid/TRS
Assembly (4.7L)GY Left Side of Transmission 16
Underhood Lamp BK At Lamp 6
Vehicle Information Center BK In Overhead Console N/S
Viscous/Cabin Heater (Diesel) BK Left Rear of Engine Compartment N/S
Washer Fluid Level Switch GY Left Front of Engine Compartment 3, 4
Wastegate Solenoid (Diesel) Near Power Distribution Center N/S
Water In Fuel Sensor (Diesel) BK Left Rear of Engine Compartment N/S
GROUNDS
GROUND NUMBER LOCATION FIG.
G100 (4.0L and Diesel) Near Starter N/S
G100 (4.7L) Near Intake Plenum N/S
G101 Near Battery 2
G102 Right Side of Engine 14, 15
G103 Right Side of Engine 7, 8, 10, 11, 14, 15
G104 (4.0L) Right Rear of Engine 10, 11
G104 (4.7L) Left Side of Engine 13
G105 Right Side of Engine 8
G106 Left Side of Engine Compartment 3, 4
G107 Left Side of Engine Compartment 3, 4
G108 Near Power Distribution Center 5
G200 Near Airbag Control Module 19, 20, 21, 22
G201 Near Airbag Control Module 19, 20, 21, 22
G300 Near Right Front Seat 34, 36
G301 Near Left Front Seat 33, 35
WJ8W-91 CONNECTOR/GROUND/SPLICE LOCATION 8W - 91 - 11
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

SPLICES
SPLICE
NUMBERLOCATION FIG.
S100 Near T/O for Power Distribution Center Eyelet 2
S102 (4.0L) Near T/O for G103 10, 11
102 (4.7L) Near T/O for Fuel Injector No. 1 13
S102 (Diesel) Near T/O for C110 7, 8
S103 (4.7L) Near T/O for Engine Oil Pressure Sensor 13
S104 (4.0L) Near T/O for A/C Compressor Clutch N/S
S104 (4.7L) Near T/O for Oxygen Sensor 2/2 Downstream N/S
S105 (4.0L) Near T/O for Capacitor 10 11
S105 (4.7L) Near T/O for Fuel Injector NO. 7 13
S106 (4.0L) In T/O for Oxygen Sensors 11, 12
S106 (4.7L) Near T/O for C103 14
S106 (4.7L) RHD Near T/O for Fuel Injector No.4 15
S107 (4.0L) Near T/O for Fuel Injector No.5 9
S107 (4.7L) Near T/O for Fuel Injector No.7 13
S109 (4.0L) Near T/O for Fuel Injector No.2 9
S109 (4.7L) Near T/O for Coil On Plug No. 6 14, 15
S110 (4.0L
Except
Built-Up-Export)Near T/O for Oxygen Sensor N/S
S111 (4.7L) In T/O for Oxygen Sensor N/S
S111 (4.0L
Except
Built-Up-Export)Near T/O for Oxygen Sensor N/S
S112 (4.0L) Near T/O for C102, C103 and C104 10, 11
S112 (4.7L) Near T/O for Coil On Plug No.8 15
S112 (Diesel) Near T/O for Accelerator Pedal Position Sensor N/S
S113 (4.7L) Near T/O for Transmission Control Module 15, 18
S114 (4.0L) Near T/O for Transmission Control Module 18
S114 (4.7L) Near T/O for Transmission Control Module 15, 18
S115 (4.0L) Near T/O for Transmission Control Module 18
S115 (4.7L) Near T/O for Transmission Control Module 15, 18
S116 (4.0L) Near Powertrain Control Module C1 and C2 18
S116 (4.7L) LHD Near T/O for C102, C103 and C104 14
S116 (4.7L) RHD In T/O for Powertrain Control Module 15
S117 (4.7L) LHD Neat T/O for C102, C103 and C104 14
S118 (4.7L) Near T/O for Coil On PlugNo.4 14, 15
S118 (Diesel) Near T/O for Fuel Sender Unit N/S
S119 (4.7L) LHD In T/O for Crankshaft Position Sensor 18
S119 (4.7L) RHD In T/O for Powertrain Control Module 15
S120 (4.7L) Near T/O for Powertrain Control Module 15, 18
S121 (4.7L) Near T/O for Idle Air Control Motor 13
8W - 91 - 12 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONWJ
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

SPLICE
NUMBERLOCATION FIG.
S122 (4.0L) Near T/O for G103 10, 11
S122 (4.7L) LHD Near T/O for Input Speed Sensor 15
S122 (4.7L) RHD Near T/O for Powertrain Control Module 16
S122 (Diesel) Near T/O for Generator N/S
S123 (4.0L) Near T/O for Capacitor 10, 11
S124 (4.7L) In Trough Near T/O for Capacitor No.2 13
S125 (Diesel) In T/O for C103 and C105 Left Rear of Engine Compartment N/S
S125 (Gas) Near T/O for Powertrain Control Module - C3 N/S
S126 (4.0L) LHD Near T/O for Battery Temperature Sensor N/S
S126 (4.0L) RHD In Trough Near T/O for Powertrain Control Module - C3 N/S
S127 (LHD) Gas In Trough Near T/O for Powertrain Control Module - C3 N/S
S127 (RHD) Gas In T/O for Power Distribution Center 5
S127 (Diesel) Near T/O for Power Distribution Center 4
S128 (Diesel) In T/O for C102 Left Rear of Engine Compartment N/S
S128 (LHD) Gas In Trough Near T/O for Powertrain Control Module - C3 N/S
S128 (RHD) Gas In T/O for C102 5
S130 (LHD) Gas In T/O for C102 N/S
S130 (RHD) Gas In T/O for Controller Antilock Brake 3
S130 (Diesel) In T/O for Controller Anti-Lock Brake 4
S131 In Trough Near T/O for Power Distribution Center 5
S131 (Diesel) Near T/O for Power Distribution Center 4
S132 (Diesel) Near T/O for EGR Solenoid N/S
S132 (Gas) Near T/O for Battery Temperature Sensor 5
S133 (Diesel) In Trough Near T/O for EGR Solenoid N/S
S133 (Gas) Near T/O for Battery Temperature Sensor 5
S134 (Diesel) In Trough Near T/O for G106/G107 4
S134 (Gas) In Trough Near T/O for Controller Anti-Lock Brake 3
S135 (Diesel) Near T/O for Engine Control Module C1 7, 8
S136 (Diesel) Near T/O for Engine Control Module C1 7, 8
S137 (Diesel) In Trough Near T/O for Coolant Level Sensor N/S
S139 (Diesel) Near T/O for Engine Control Module C1 7, 8
S140 (Diesel) Near T/O for Power Distribution Center 4
S140 (Gas) Near T/O for Controller Antilock Brake N/S
S141 (Gas) Near T/O for Controller Antilock Brake 3
S142 (Diesel) In Trough Near T/O for Coolant Level Sensor N/S
S142 Gas In T/O for C102 5
S143 (Diesel) In Trough Near T/O for Hood Ajar Switch 4
S143 (Gas,
Built-Up-Export)
LHDIn Trough Near T/O for Controller Antilock Brake 3
S143 Gas RHD Near T/O for Evap/Purge Solenoid N/S
S145 (Diesel) Near T/O for Engine Control Module C1 7, 8
WJ8W-91 CONNECTOR/GROUND/SPLICE LOCATION 8W - 91 - 13
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

8W-97 POWER DISTRIBUTION
TABLE OF CONTENTS
page page
POWER DISTRIBUTION
DESCRIPTION..........................1
OPERATION............................1
SPECIAL TOOLS
POWER DISTRIBUTION SYSTEMS.........2
CIGAR LIGHTER OUTLET
DESCRIPTION..........................2
OPERATION............................2
DIAGNOSIS AND TESTING - CIGAR LIGHTER
OUTLET.............................2
CIGAR LIGHTER OUTLET DOOR SPRING
REMOVAL.............................3
INSTALLATION..........................3
IOD FUSE
DESCRIPTION..........................3
OPERATION............................4
REMOVAL.............................4
INSTALLATION..........................4
JUNCTION BLOCK
DESCRIPTION..........................5
OPERATION............................5
REMOVAL.............................5
INSTALLATION..........................6
POWER DISTRIBUTION CENTER
DESCRIPTION..........................7
OPERATION............................8
REMOVAL.............................8
DISASSEMBLY
POWER DISTRIBUTION CENTER
DISASSEMBLY........................9ASSEMBLY
POWER DISTRIBUTION CENTER
ASSEMBLY..........................11
INSTALLATION.........................12
POWER OUTLET
DESCRIPTION - FRONT POWER OUTLET....12
OPERATION - FRONT POWER OUTLET......12
DIAGNOSIS AND TESTING - POWER OUTLET . 12
REMOVAL.............................13
INSTALLATION.........................13
POWER OUTLET RELAY
DESCRIPTION.........................13
OPERATION...........................14
DIAGNOSIS AND TESTING - POWER OUTLET
RELAY..............................14
REMOVAL.............................15
INSTALLATION.........................15
IOD WIRE HARNESS CONNECTOR
DESCRIPTION.........................15
OPERATION...........................15
FUSE COVER
REMOVAL.............................16
INSTALLATION.........................16
REAR POWER OUTLET
DESCRIPTION - REAR POWER OUTLET.....16
OPERATION - REAR POWER OUTLET.......17
DIAGNOSIS AND TESTING - REAR POWER
OUTLET............................17
REMOVAL.............................17
INSTALLATION.........................18
POWER DISTRIBUTION
DESCRIPTION
This group covers the various standard and
optional power distribution components used on this
model. The power distribution system for this vehicle
consists of the following components:
²Power Distribution Center (PDC)
²Junction Block (JB)
²Power Outlets
The power distribution system also incorporates
various types of circuit control and protection fea-
tures, including:
²Automatic resetting circuit breakers
²Blade-type fuses
²Bus bars
²Cartridge fuses²Circuit splice blocks
²Flashers
²Fusible links
²Standard and Micro-Relays
Following are general descriptions of the major
components in the power distribution system. See the
owner's manual in the vehicle glove box for more
information on the features and use of all of the
power distribution system components. Refer to Wir-
ing Diagrams for complete circuit diagrams.
OPERATION
The power distribution system for this vehicle is
designed to provide safe, reliable, and centralized dis-
tribution points for the electrical current required to
operate all of the standard and optional factory-in-
stalled electrical and electronic powertrain, chassis,
safety, security, comfort and convenience systems. At
WJ8W-97 POWER DISTRIBUTION 8W - 97 - 1