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

LH Front of Vehicle


Object Number: 310802  Size: MF
(1)Upper Radiator Support -Tie Bar
(2)Headlamp Assembly-LF
(3)Headlamp - High Beam - Left Connector
(4)Daytime Running Lamp (DRL)-Left
(5)Daytime Running Lamp (DRL)-Left Socket
(6)Windshield Washer Reservoir
(7)Park/Turn Signal Lamp Socket-LF
(8)Marker Lamp Socket-LF
(9)Marker Lamp-LF
(10)Park/Turn Signal Lamp-LF
(11)Snowplow Connector C125-Option
(12)Headlamp Connector-Low Beam-Left
(13)Marker Lamp-LF
Figure 2:

C103


Object Number: 310806  Size: MF
(1)Fuse Block-Underhood Bracket
(2)Inflatable Restraint Harness
(3)Radiator Support
(4)Inline Connector-C103-I/P Harness Side
(5)Inline Connector-C103-Forward Lamp Harness Side
(6)LH Battery Tray
(7)Fuse Block-Underhood Bracket
(8)Fuse Block-Underhood
Figure 3:

C104, C114, C150, C151, C153, C154, and PTO Relay


Object Number: 814636  Size: LF
(1)Fuse Block - Underhood
(2)C153 - Engine Harness to Transfer Case Harness
(3)C150 - Transfer Case Harness to Axle Jumper Harness
(4)Transfer Case Harness
(5)C151 - I/P Harness to Automatic Transfer Case Harness (w/NP8/NR4) or C104 - I/P Harness to Forward Lamp Harness (w/o NP8/NR4)
(6)C154 - I/P Harness to Automatic Transfer Case Harness (w/NP8/NR4) or C114 - Chassis Harness to I/P Harness (w/JL4/NYS)
(7)Power Take-Off (PTO) Relay
Figure 4:

C148 and C149


Object Number: 1404000  Size: LF
(1)C149 Engine Harness to Even Ignition Coil Harness
(2)C148 Engine Harness to Odd Ignition Coil Harness
(3)Throttle Body
Figure 5:

Inline Connectors Under the Fuse Block-Underhood


Object Number: 413351  Size: MF
(1)Inline Connector-C102
(2)Fuse Block-Underhood Support/Mount
(3)Inline Connector-C152
(4)Inline Connector-C100
Figure 6:

Engine Harness Connector Locations-8.1L


Object Number: 656555  Size: LF
(1)MAP Switch Connector
(2)Surge Tank Switch Connector
(3)Secondary Air Injection (AIR) Solenoid Relay Connector
(4)Secondary Air Injection (AIR) Pump Connector
(5)MAP Sensor Connector
(6)A/C Compressor Connector
(7)Engine Wiring Harness Ground
(8)Oil Pressure Sensor Connector
(9)Oil Pressure Sensor Connector
(10)Starter Connector
(11)Knock Sensor Connector
(12)Automatic Transmission Input Speed Sensor (ISS) Connector
(13)Oxygen Sensor Connector
(14)Turbine Shaft Speed (TSS) Sensor Connector
(15)Oxygen Sensor Connector
(16)Power Take Off (PTO) Connector
(17)Transmission Harness Connector
(18)Speed Sensor Connector
(19)Park/Neutral Position (PNP) Switch Connectors
(20)Oxygen Sensor Connector
(21)Low Oil Level Sensor Connector
(22)Crankshaft Position Sensor Connector
(23)Knock Sensor Connector
(24)Ignition Coil Connector
(25)Engine Wiring Harness Ground
(26)Camshaft Position Sensor Connector
(27)Powertrain Control Module (PCM) Connectors
(28)Power Take Off (PTO) Relay Connector
(29)Inline to IP Harness Connector
(30)Inline to Chassis Harness Connector
(31)Junction Block-Underhood
(32)Transmission Control Module Connectors (M74)
(33)Throttle Actuator Control (TAC) Module Connector
(34)Throttle Position (TP) Sensor Connector
(35) Generator Connector
(36)Fuel Injector Connector
(37)Electric Throttle Control Connector
Figure 7:

I/P Harness Routing - Left Side of I/P Console


Object Number: 1463258  Size: LF
(1)C202 I/P Harness to Brake/Clutch Harness
(2)C214 I/P Harness to Headliner Harness (w/UE1/U42)
(3)C214 I/P Harness to Headliner Harness (w/UE1/U42)
(4)G203 (1851)
(5)C203 I/P to Left Front Door Harness (w/JF4)
(6)C221 I/P Harness to Body Harness
(7)C204 I/P Harness to Body Harness
(8)Splice Pack SP250 (w/UQ7)
(9)C201 I/P Harness to Steering Column Harness
(10)C275 I/P Harness to Inflatable Restraint Steering Wheel Module
(11)Splice Pack SP205
Figure 8:

I/P Harness Routing - Right Side of I/P Console


Object Number: 1463262  Size: LF
(1)C306 I/P Harness or Infotainment Jumper Harness to Console Harness
(2)C249 I/P Harness to Info Jumper Harness (Except Y91)
(3)C230 I/P Harness to Roofmarker Harness
(4) I/P Harness to Roof Marker Coax
(5)C231 I/P Harness to Diversity Antenna Harness (Z75 except EXT)
(6)Fuse Block - Right I/P C1
(7)C222 I/P Harness to Body Harness
(8)C209 I/P Harness to Body Harness
Figure 9:

HVAC Module Assembly (Connections)


Object Number: 310004  Size: MF
(1)Recirculation Actuator Connector
(2)Instrument Panel
(3)Electrical Harness Connector
(4)Ground 200 (G200)
(5)Blower Motor Resistor Assembly
(6)Blower Motor Resistor Connector
(7)Harness Inline Connector (C296)
(8)Air Temperature Actuator Connector
(9)Air Temperature Actuator
(10)Mode Actuator
Figure 10:

Lower RF of the Passenger Compartment


Object Number: 926693  Size: MF
(1)C222
(2)C315 (AJ7)
(3)Body Harness
(4)C209
Figure 11:

C210 and Relay Block-Body-C4


Object Number: 814939  Size: LF
(1)Relay Block-Body
(2)Relay Block-Body-C4
(3)C210-Roof Beacon Relay Inline
Figure 12:

C306 - Avalanche/Suburban


Object Number: 813723  Size: MF
(1)C306
(2)Front Floor Console Extension
(3)Speaker - Subwoofer
(4)I/P Harness
Figure 13:

Driver Seat (1 of 2)


Object Number: 854624  Size: LF
(1)C321
(2)Seat Adjuster Switch - Driver
(3)Memory Seat Module - C4
(4)Memory Seat Module - C3
(5)Seat Bolster/Lumbar Switch - Driver
(6)Seat Recliner Motor - Driver
(7)C305
(8)C323
(9)C325
(10)C322
(11)Seat Rear Vertical Motor - Driver
(12)Seat Front Vertical Motor - Driver
(13)Memory Seat Module - C2
(14)Memory Seat Module - C1
(15)Seat Horizontal Motor - Driver
(16)C320
Figure 14:

Driver Seat (2 of 2)


Object Number: 854618  Size: LF
(1)Seat Bolster Motor - Driver
(2)Seat Lumbar Motor - Driver
(3)Heated Seat Element - Driver Cushion
(4)C324
(5)Seat Belt Switch Connector
(6)Heated Seat Element - Driver Cushion Connector
Figure 15:

Front Passenger Seat (1 of 2) (w/ AN3)


Object Number: 854616  Size: LF
(1)Seat Horizontal Motor - Front Passenger
(2)Seat Front Vertical Motor - Front Passenger
(3)Seat Rear Vertical Motor - Front Passenger
(4)C388
(5)C326
(6)C399
(7)Seat Recliner Motor - Front Passenger
(8)Seat Adjuster Switch - Front Passenger
(9)Seat Adjuster Switch Connector
Figure 16:

Front Passenger Seat (2 of 2) (w/ AN3)


Object Number: 854613  Size: LF
(1)Seat Bolster Motor - Front Passenger
(2)Seat Lumbar Motor - Front Passenger
(3)Heated Seat Element - Front Passenger Cushion Connector
(4)C329
Figure 17:

C327


Object Number: 814871  Size: MF
(1) Seat-LR
(2)C327-Inline to Rear Seat Harness
(3)LH Body Harness
Figure 18:

Right Body Harness to Rear Seat Harness


Object Number: 741070  Size: MF
(1)Rear Seat
(2)Rear Seat Harness Connector (Inline C349)
(3)Right Body Harness Connector (Inline C349)
(4)Right Body Harness
Figure 19:

C388


Object Number: 814876  Size: MF
(1)Seat-RR
(2)C388-Inline to Seat Harness-RR
Figure 20:

Rear Audio Console Harness Connectors


Object Number: 623128  Size: MF
(1)Front Floor Compartment
(2)I/P Harness
(3)Inline Connector 307 (Uplevel Utility), Inline 340 (Luxury Utility)
(4)Inline Connector 307 (Uplevel Utility), Inline 340 (Luxury Utility)
(5)Console Harness
(6)Inline Connector 314 (Rear Console Harness Side)
(7)Inline Connector 314 (LH body Harness Side)
Figure 21:

C314 and C341-LH Body Harness to Console


Object Number: 813764  Size: LF
(1)C341-Avalanche (53 Similar)
(2)Left Body Harness
(3)C314-Left Body Harness Side-Luxury Utility
(4)C314-Console Harness Side-Luxury Utility
Figure 22:

Rear Audio Extension Harness Connectors


Object Number: 623121  Size: MF
(1)Instrument Panel
(2)Radio Connectors
(3)Console Extension Harness
(4)Inline Connector 253 (IP Harness Side)
(5)Inline Connector 253 (Console Extension Harness Side)
(6)Compact Disc Player Connector
(7)Front Floor Console Extension
(8)Instrument Panel Harness
(9)Radio
Figure 23:

Rear HVAC Harness


Object Number: 573929  Size: LF
(1)Inner Body Side Panel
(2)Splice Pack 410 (SP410)
(3)Splice Pack 410A (SP410A)
(4)Blower Motor Connector
(5) HVAC Assembly - Auxiliary
(6)Air Temperature Sensor-Lower Auxiliary
(7)Mode Actuator-Auxiliary Connector
(8)Inline Connector 350 -Auxiliary HVAC Harness Side
(9)Inline Connector 350 -Headliner Harness Side
(10)Inline Connector 397 -Auxiliary HVAC Harness Side
(11)Inline Connector 397 -RH Body Harness Side
Figure 24:

Body Harness Rear RH


Object Number: 574004  Size: MF
(1)Back Body Opening Inner Upper Panel
(2)CHSML Cargo
(3) Door Lock Switch Rear Cargo
(4)Splice Pack 410
(5)Speaker - RR Connector
(6)Inline to Headliner
Figure 25:

Body Harness Rear LH


Object Number: 574001  Size: LF
(1)Body Side Inner Panel
(2)Body Harness-LH
(3)Speaker- Subwoofer Connector
(4)Speaker-LR -D Pillar
Figure 26:

Rear Body Harness - Avalanche/Esclade EXT


Object Number: 1688645  Size: MF
(1)C392
(2)Rear Window Defogger - Ground
(3)C390
(4)Rear Window Defogger - Power
(5)C415 (Z75)
(6)Passthrough to Chassis Harness (Z75)
(7)Body Harness
(8)C450 (Z75)
(9)Cargo Lamp - Driver (RH Similar)
Figure 27:

C402


Object Number: 814537  Size: MF
(1)C402-Chassis Harness Side
(2)C402-Tail Lamp Harness Side
Figure 28:

Chassis Wiring Harness to Rear Side Rail-LH


Object Number: 615821  Size: MF
(1)Inline Connector C405 to Tail Lamp Harness
(2)Shock Absorber Solenoid Connector-RR
(3)Frame
(4)Inline Connector C450
(5)Chassis Harness
Figure 29:

C406 and P475-Escalade/Avalanche EXT w/VSES


Object Number: 814880  Size: MF
(1)P475
(2)C406-RH Body Harness Side
(3)C406-Tail Lamp Harness Side
(4)Junction Block-C3-Rear Lamps
Figure 30:

Real Time Damping Connector to Body Wiring Harness


Object Number: 615767  Size: MF
(1)Inline Connector C450 -Chassis Harness Side
(2)Inline Connector C450 -Body Harness Side
(3)Frame
Figure 31:

Liftgate Wiring Harness to Liftgate


Object Number: 573926  Size: LF
(1)Liftgate with Liftglass
(2)Liftglass Defog Connector
(3)Liftgate Latch Connector
(4)Liftgate Lower Latch Connector
(5)Liftgate Latch Connector
(6)Liftgate Lower Latch Connector
(7)Liftgate Latch Connector
(8)Wiper Motor Connector
(9)Inline Connector C499
Figure 32:

Rear Lamp Harness to Rear License Plate/Tail Lamp Harness-RH (LH Similiar)


Object Number: 623153  Size: MF
(1)Back Body Opening Lower Frame
(2)Rear Lamp Wiring Harness
(3)Inline Connector 403 -Rear Lamp Harness Side
(4)Inline Connector 403 -Tail Lamp Harness Side
(5)Inline Connector 404 -Rear Lamp Harness Side
(6)Inline Connector 404 -Rear License Plate Harness Side
(7)License Plate Wiring Harness
Figure 33:

Junction Block-Rear Lamps-C1 and C2


Object Number: 814544  Size: MF
(1)C2-Gray
(2)Body Panel-RH Side
(3)Junction Block-Rear Lamps
(4)C1-Blue
Figure 34:

Junction Block-Rear Lamps-C3 and C4


Object Number: 814020  Size: MF
(1)Junction Block-Rear Lamps-Utility
(2)C4-Tail Lamp Harness -RH
(3)C3-Rear License Lamp Harness-RH
Figure 35:

Auxiliary Power Center - 9L4


Object Number: 1410792  Size: LF
(1)Underhood Fuse Block
(2)Battery
(3)40A Mega Fuse
(4)C117
(5)Accessory Jumper Harness
(6)C119
(7)I/P Carrier
(8)Auxiliary Power Harness
(9)C216
(10)Brake/Clutch Harness
(11)Passthrough P101
(12)I/P Relay Block
(13)Auxiliary Power Fuse/Relay Block
(14)Glove Box Opening
(15)C5
(16)I/P Relay Block
(17)C8
Figure 36:

Roof Lamp Wiring Provisions - 5G4


Object Number: 1411842  Size: LF
(1)Blunt Cut Wires for Roof Light
(2)Roof Light Switch
(3)C250
(4)I/P Jumper Harness
(5)Roof Light Relay
(6)G305
(7)C210
(8)Relay Block C8
(9)Relay Block C9
(10)Relay Block - I/P
(11)Brake/Clutch Harness