GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Dash Wiring-Top Left


Object Number: 290830  Size: LF
(1)S222, S225, S226
(2)G200
(3)Park Brake Pull Button Switch Connector
(4)C203
(5)C202
(6)S227, S228, S229, S230, S231, S232
(7)Steering Column
(8)Fuse Block (located by body builder)
(9)Transmission Range (TR) Shift Control Connector
(10)S211, S212, S213
(11)Daytime Running Lamps (DRL) Diode Module Connector
(12)Steering Column Connector
(13)Diode Network
(14)Speedometer Adapter Module Connector
(15)S215, S216, S217, S219, S220, S236
(16)S200
(17)DRL Control Module
(18)S201, S202, S203, S204, S205, S206
(19)S221
(20)S207, S208, S209, S210
(21)Park Brake Alarm (located by body builder)
Figure 2:

Dash Wiring-Lower Left


Object Number: 290827  Size: LF
(1)Steering Column Support
(2)Throttle Actuator Control (TAC) Module Connector C2
(3)Throttle Actuator Control (TAC) Module Connector C1
(4)Data Link Connector (DLC)
(5)IP Wiring Harness Junction Block
(6)C101
(7)C113
(8)C104
Figure 3:

IP Wiring Harness Junction Block, Front View


Object Number: 264262  Size: MF
(1)Multifunction Alarm Module
(2)Hazard/Turn Signal Flasher
(3)Daytime Running Lamps (DRL) Relay
(4)Park Brake Pull Button Switch Relay
Figure 4:

Engine Harness Right Front


Object Number: 240962  Size: LF
(1)S101
(2)S105
(3)G102
(4)Manifold Absolute Pressure (MAP) Sensor
(5)Crankshaft Position (CKP) Sensor
(6)Generator
(7)Throttle Position (TP) Sensor
(8)G103, G104, G109
(9)Engine Coolant Temperature (ECT) Sensor
(10)C103
(11)Throttle Actuator Motor
(12)S100
(13)S103
(14)S102
(15)Engine Harness
Figure 5:

Engine Harness to IP Harness


Object Number: 240960  Size: LF
(1)Park Brake Pull Button Switch
(2)Powertrain Control Module (PCM)
(3)PCM Connector C1
(4)PCM Connector C2
(5)S110
(6)S113
(7)S114
(8)S115
(9)IP Wiring Harness Junction Block
(10)S116
(11)C100
(12)C104
(13)C101
(14)C113
(15)Engine Wiring Harness Junction Block (Underhood Fuse Relay Center)
(16)P100
(17)Speedometer Adapter Module
(18)Daytime Running Lamps (DRL) Diode Module
Figure 6:

Engine Wiring Harness Junction Block (Underhood Fuse Relay Center), Front View


Object Number: 277438  Size: LF
(1)Park Brake Actuator Position Switch Relay
(2)Horn Relay
(3)Fuel Pump Relay
(4)A/C Relay
(5)Starter Relay
(6)Brake Lamp Relay
(7)Fuse Puller and Spare Fuses
(8)Hot at All Times B+ Feed
(9)Auxiliary Power Studs
Figure 7:

Rear of Cowl and Steering Column Support


Object Number: 258722  Size: LF
(1)Park Brake Pull Button Switch
(2)Windshield Wiper Pulse Control Module
(3)Powertrain Control Module (PCM)
(4)PCM Connector C1
(5)PCM Connector C2
(6)Accelerator Pedal Position (APP) Sensor
(7)Stoplamp Switch
(8)IP Wiring Harness Junction Block
(9)Steering Column Connector
(10)Ignition Switch
(11)Transmission Range Shift Control
Figure 8:

Radiator Support Wiring


Object Number: 240952  Size: MF
(1)Power Brake Booster Pump
(2)S122
(3)S123
(4)Power Brake Booster Pump Relay
(5)S120
(6)Power Brake Booster Pump Motor
(7)S121
(8)S117, S118
(9)ABS Module
(10)S119
(11)G101
(12)RH Wheel Speed Sensor
(13)Intake Air Temperature (IAT) Sensor
(14)Engine Coolant Level Switch
(15)Engine Coolant Surge Tank
(16)Powertrain Control Module (PCM)
(17)Power Brake Booster Fluid Flow Indicator Switch
Figure 9:

Park Brake Harness Connections and Grounds


Object Number: 317451  Size: SF
(1)S302
(2)Rear Chassis Harness
(3)C300
(4)G300, G400
(5)C301
(6)S306, S307, S308, S309
(7)S303, S304, S305
(8)S407
(9)Auto Apply Park Brake Harness