GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Express 🢒 Engine 🢒 Engine Electrical 🢒 Harness Routing Views
Figure 1:

Forward Lamp Wiring
Object Number: 323359 Size: MF
(1)G109
(2)C111
(3)C102
(4)G108
Figure 2:

Inflatable Restraint Forward Wiring
Object Number: 375567 Size: MF
(1)C114
Figure 3:

Forward Lamp Wiring, Horns
Object Number: 323365 Size: MF
(1)G108
(2)C102
(3)C111
(4)R100
Figure 4:

Generator Wiring
Object Number: 375571 Size: MF
(1)C 115
(2)Generator, 100 Amp
(3)Generator, 124 Amp
Figure 5:

P/B Booster System Wiring
Object Number: 323371 Size: MF
(1)P103
(2)C113
(3)G112
(4)G108
Figure 6:

4.3L Engine Harness, Right Side
Object Number: 323373 Size: MF
(1)C110
(2)G103
Figure 7:

Engine, Upper RH Side (5.0L, 5.7L)
Object Number: 375573 Size: MF
(1)C112
(2)A/C Compressor Clutch
(3)Exhaust Gas Recirculation (EGR) Valve
(4)Engine Coolant Temperature (ECT) Sensor
(5)Evaporative Emission (EVAP) Canister Vacuum Switch
(6)C110
(7)Ignition Control Module
(8)Ignition Coil
(9)Fuel Injectors (1-8)
(10)Manifold Absolute Pressure (MAP) Sensor
Figure 8:

7.4L Engine Harness, Rear
Object Number: 323396 Size: MF
(1)C110
(2)C112
(3)G103
Figure 9:

Glow Plug Controller (Federal)
Object Number: 395118 Size: MF
(1)Glow Plug Relay (Federal)
Figure 10:

Automatic Transmission, 4-Speed, 4L60-E
Object Number: 375600 Size: MF
(1)C 103
(2)Vehicle Speed Sensor (VSS)
(3)Park/Neutral Position Switch
Figure 11:

Automatic Transmission, 4-Speed, 4L80-E
Object Number: 327364 Size: MF
(1)Vehicle Speed Sensor (VSS)
(2)Park/Neutral Position Switch
(3)Backup Lamp Switch (Part of Park/Neutral Position Switch)
(4)Automatic Transmission Input Shaft Speed (A/T ISS) Sensor
Figure 12:

Oxygen Sensor Wiring (5.0L, 5.7L, 7.4L Engines)
Object Number: 375606 Size: MF
(1)Heated Oxygen Sensor Bank 1, Sensor 2
(2)Heated Oxygen Sensor Bank 2, Sensor 2
(3)Catalytic Converter
(4)Heated Oxygen Sensor Bank 1, Sensor 1
(5)C105
(6)Heated Oxygen Sensor Bank 2, Sensor 1
Figure 13:

Wheel Speed Sensor Wiring
Object Number: 173451 Size: MF
(1)Wheel Speed Sensor, LF
(2)Wheel Speed Sensor, RF
(3)Connector C3
(4)Electronic Brake Control Module (EBCM)
Figure 14:

Electronic Brake Control Module
Object Number: 173447 Size: MF
(1)Electronic Brake Control Module (EBCM)
(2)Ignition Feed (C1)
(3)Wheel Sensor (C2)
(4)Brake Pressure Differential Switch
(5)Battery (C3)
Figure 15:

Fuel Pump Wiring
Object Number: 375609 Size: MF
(1)C301
(2)Electronic Brake Control Module (EBCM)
(3)Fuel Lift Pump
Figure 16:

Instrument Panel Wiring, Forward of Dash
Object Number: 345355 Size: MF
(1)Vehicle Control Module (VCM)
(2)Cruise Control Module
(3)P102
(4)Windshield Wiper Motor
Figure 17:

Bulkhead Connector Harness View
Object Number: 323404 Size: MF
(1)C100
(2)P100
Figure 18:

Antenna
Object Number: 344437 Size: MF
(1)Antenna
(2)P104
Figure 19:

Instrument Panel, Radio
Object Number: 344444 Size: MF
(1)Radio Antenna Lead
(2)Radio
(3)C204
Figure 20:

Steering Column Wiring
Object Number: 375631 Size: MF
(1)Steering Column Harness
(2)C200
(3)C218
(4)Steering Column
Figure 21:

IP Fuse Block Wiring
Object Number: 323408 Size: MF
(1)P103
(2)C100
(3)G202
(4)G201
Figure 22:

Instrument Panel Wiring
Object Number: 375637 Size: MF
(1)C206
(2)C208
(3)C201
(4)C405
Figure 23:

Convenience Center Connectors
Object Number: 323413 Size: MF
(1)C202
(2)C207
(3)C210
Figure 24:

Power Brake Fluid Flow Alarm And Module
Object Number: 173462 Size: MF
(1)Resistor R208
(2)P/B Booster Fluid Flow Alarm
(3)Diode D202
(4)Connector C208
(5)Connector C201
(6)Park Brake Warning Switch
(7)P/B Booster Fluid Flow And Pressure Alarm Delay Module (Cutaway-School Bus)
Figure 25:

Front Crossbody Wiring (Right)
Object Number: 323416 Size: MF
(1)C212
(2)C300
Figure 26:

Accessory Wiring Harness
Object Number: 323420 Size: MF
(1)C409
(2)C415
(3)P103
(4)C302
Figure 27:

LH Wiring View
Object Number: 375643 Size: MF
(1)C215
(2)C209
Figure 28:

Sunshade Illuminated Mirror Wire
Object Number: 323422 Size: MF
(1)C303
(2)C214
Figure 29:

Front Side Door Wiring, Left
Object Number: 344453 Size: MF
(1)Power Outside Rearview Mirror, Interface Cable
(2)P500, P600 (Right)
(3)C211, C212 (Right)
(4)Radio Speaker, Left Door (Right Opposite)
Figure 30:

Dome Lamp Wiring
Object Number: 323424 Size: LF
(1)C417
(2)C405
Figure 31:

Auxiliary Heater and A/C Wiring
Object Number: 375651 Size: MF
(1)C407
(2)Auxiliary Blower Motor High Speed Relay
(3)Auxiliary Blower Motor Medium Speed Relay
(4)Auxiliary Blower Motor Low Speed Relay
(5)Auxiliary Blower Motor
(6)Rear Auxiliary Mode Valve and Seal Assembly (Mode Door Motor)
(7)Rear Auxiliary Temperature Valve Assembly (Temperature Door Motor)
(8)Auxiliary Blower Motor Resistor
(9)C408
Figure 32:

Left Body Wiring
Object Number: 323425 Size: MF
(1)G400
(2)C404
(3)C411
(4)C408
(5)C407
(6)C406
(7)C402
(8)G401
(9)C401
(10)G402
Figure 33:

Radio Rear Speaker Wiring
Object Number: 344455 Size: MF
(1)Right Body Harness
(2)C415
(3)Left Body Harness
(4)Radio Speaker, Right Overhead
(5)Radio Speaker, Left Overhead
(6)C403
Figure 34:

Trailer Wiring
Object Number: 375652 Size: MF
(1)P400
(2)C406
Figure 35:

Right Rear Door Wiring (LH Similar), Radio Speaker
Object Number: 344457 Size: MF
(1)C412
(2)License Lamp
(3)Door Jamb Switch, Right Rear
(4)Door lock Actuator Motor, Rear
(5)Radio Speaker, Right Rear Door (Left Rear Door Opposite)
(6)P901 RH, P902 LH
(7)C402
(8)C400 RH
Figure 36:

Taillamp Assembly Wiring
Object Number: 323428 Size: MF
(1)P903 LH, P904 RH
(2)C401 RH, C404 LH
Figure 37:

C419
Object Number: 323431 Size: MF
(1)C419
Figure 38:

P400
Object Number: 323433 Size: MF
(1)P400