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

Forward Lamp Harness Routing


Object Number: 1557126  Size: LF
(1)Horn Assembly
(2)C118
(3)Ambient Air Temperature Sensor
(4)Headlamp Washer Fluid Pump (CE4)
(5)A/C Low Pressure Switch
(6)G103
(7)Park/Turn Signal Lamp - RF
(8)Marker Lamp - RF
(9)C103
(10)S103
(11)Rear Window Washer Fluid Pump
(12)Fog Lamp - RF
(13)Windshield Washer Fluid Pump
(14)S113
(15)Windshield Washer Fluid Level Switch
(16)Fog Lamp - LF
(17)S107
(18)Park/Turn Signal Lamp - LF
(19)C102
(20)Marker Lamp - LF
(21)Fuse Block - Underhood C4
(22)C105
Figure 2:

Chassis Harness Routing


Object Number: 1703423  Size: LF
(1)Electronic Frontal Sensor (EFS) - Right
(2)Wheel Speed Sensor - RF
(3)Electronic Brake Control Module (EBCM)
(4)C310
(5)Vehicle Speed Sensor (VSS)
(6)S306
(7)Fuel Pump and Sender Assembly
(8)Evaporative Emission (EVAP) Canister Vent Solenoid
(9)Air Suspension Sensor - RR
(10)Air Suspension Compressor Assembly C1
(11)G403
(12)Air Suspension Sensor - LR
(13) Fuel Tank Pressure (FTP) Sensor
(14)S359 (5.3L)
(15)G305
(16)Propshaft Speed Sensor - Rear
(17)Transfer Case Encoder Motor
(18) Propshaft Speed Sensor - Front
(19)G304
(20)Wheel Speed Sensor - LF
(21)C101
(22)Fuse Block - Underhood C3
(23)Fuse Block - Underhood C7
(24)Electronic Frontal Sensor (EFS) - Left
Figure 3:

Body Harness Routing


Object Number: 1558188  Size: LF
(1)Splice Pack SP306
(2)Center High Mounted Stop Lamp (CHMSL)
(3)C900
(4)S401
(5)G401
(6)C906
(7)C304
(8)Inflatable Restraint Roof Rail Module - Left
(9)Fuse Block - Rear C2
(10)C700
(11)Air Temperature Sensor Assembly - Inside
(12)G302
(13)S302
(14)C317
(15)C500
(16)C311
(17)C306
(18)C314
(19)C318
(20)C203
(21)C202
(22)C220 (U42)
(23)C600
(24)S310
(25)S303
(26)G303
(27)C800
(28)Vehicle Communication Interface Module (VCIM) C1
(29)Vehicle Communication Interface Module (VCIM) C2
(30)Inflatable Restraint Roof Rail Module - Right
(31)S402
(32)Audio Amplifier (UQA) C2
(33)Audio Amplifier (UQA) C1
(34)C907
(35)G402
Figure 4:

Engine Harness Routing - Left Front (4.2L)


Object Number: 1779270  Size: LF
(1)Engine Coolant Temperature (ECT) Sensor
(2)Evaporative Emission (EVAP) Canister Purge Solenoid
(3)Powertrain Control Module (PCM) C3
(4)Throttle Body
(5)Manifold Absolute Pressure (MAP) Sensor
(6)Powertrain Control Module (PCM) C2
(7)C100
(8)Starter
(9)Fuse Block - Underhood C1
(10)Knock Sensor (KS) 2 - Rear
(11)Crankshaft Position (CKP) Sensor
(12)G109
(13)G101
(14)G110
(15)A/C Compressor Clutch Assembly
(16)A/C Refrigerant Pressure Sensor
(17)Knock Sensor (KS) 1 - Front
(18)G107
(19)Generator
Figure 5:

I/P Harness Routing - Engine Compartment


Object Number: 1557843  Size: LF
(1)Fuse Block - Underhood C6
(2)Fuse Block - Underhood C5
(3)G104
(4)G105
(5)S114 (CE4)
(6)G102
(7)C107 (5.3L)
(8)C105
(9)S117 (5.3L)
(10)Fuse Block - Underhood C2
(11)C101
(12)S117 (4.2L)
(13)C100 (4.2L)
(14)Powertrain Control Module (PCM) C1 (4.2L)
Figure 6:

Engine Harness Routing - Left Rear (5.3L)


Object Number: 1701037  Size: LF
(1)Generator
(2)S112
(3)Evaporative Emission (EVAP) Canister Purge Solenoid
(4)C109
(5)Fuel Injector 3
(6)Fuel Injector 5
(7)Fuel Injector 7
(8)Engine Oil Pressure (EOP) Sensor
(9)Valve Lifter Oil Manifold (VLOM) Assembly
(10)Heated Oxygen Sensor (HO2S) Bank 2 Sensor 2
(11)Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1
(12)C310
(13)Heated Oxygen Sensor (HO2S) Bank 1 Sensor 2
(14)Park/Neutral Position (PNP) Switch
(15)G107
(16)Knock Sensor (KS) 1 - Left
(17)G108
(18)C107
(19)Engine Coolant Temperature (ECT) Sensor
(20)Engine Control Module (ECM) C1
(21)Engine Control Module (ECM) C2
(22)Engine Control Module (ECM) C3
(23)Fuse Block - Underhood C1
(24)S100
(25)Brake Booster Vacuum Sensor
(26)Fuel Injector 1