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

Power, Ground, DLC, and Vehicle Speed


Object Number: 857689  Size: FS
Master Electrical Component List
Rear Wheel Steering Description and Operation
Rear Wheel Steering Switch
QS4, RADIO, RDO AMP
QS4, RADIO, RDO AMP
IGN 3, CRUISE, 4WD
SP205 - 1 of 2
Vehicle Speed Signal
Figure 2:

Rear Wheel Steering Switch


Object Number: 857690  Size: FS
Master Electrical Component List
Rear Wheel Steering Description and Operation
03 GMT800 Rear Wheel Steering SCH (Steering Wheel/Speed Position Sensor)
Power, Ground, DLC, and Vehicle Speed
LED Dimming Supply Voltage - 1 of 3
Figure 3:

Steering Wheel/Speed Position Sensor


Object Number: 896071  Size: FS
Master Electrical Component List
Rear Wheel Steering Description and Operation
YAW/LAT and Rear Wheel Position Sensors
Rear Wheel Steering Switch
IGN 3, CRUISE, 4WD
IGN 3, CRUISE, 4WD
G203-3 of 3
G203-1 of 3
G203-1 of 3
G203-2 of 3
Vehicle Theft Deterrent
Interior Lights and LED Dimming Control
Figure 4:

YAW/LAT and Rear Wheel Position Sensors


Object Number: 857691  Size: FS
Master Electrical Component List
Rear Wheel Steering Description and Operation
Steering Gear Motor Assembly
03 GMT800 Rear Wheel Steering SCH (Steering Wheel/Speed Position Sensor)
Figure 5:

Steering Gear Motor Assembly


Object Number: 857692  Size: FS
Master Electrical Component List
Rear Wheel Steering Description and Operation
YAW/LAT and Rear Wheel Position Sensors