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

Automatic 4WD Support Wiring


Object Number: 429318  Size: MF
(1)Automatic Transfer Case Control Module
(2)IP Harness
(3)Daytime Running Lights Control (DRL) Module
(4)Convenience Center
(5)IP Reinforcement Brace
Figure 2:

Automatic Transfer Case Wiring


Object Number: 583175  Size: MF
(1)Front Propshaft Speed Sensor
(2)Encoder Connector
(3)Shift Motor Connector
(4)Vehicle Speed Sensor
(5)Rear Propshaft Speed Sensor
(6)Transfer Case Housing
Figure 3:

Transfer Case Select Switch


Object Number: 183948  Size: LF
(1)Radio Connector
(2)Rear Wiper Switch
(3)Cargo Lamp Switch
(4)Rear Fan Switch
(5)Electric Shift Transfer Case Switch or Fog Lamp Switch
Figure 4:

C100, C131, C132, and P100


Object Number: 634900  Size: MF
(1)Pass Through Grommet P100
(2)Connector C100
(3)Engine Harness
(4)Connector C132
(5)Connector C131
Figure 5:

Front Axle Actuator Wiring


Object Number: 601510  Size: LF
(1)Transfer Case Harness
(2)Starter
(3)Battery Cable
(4)Front Differential
(5)Actuator Motor
(6)Actuator Connector
(7)Frame