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

Power and Front Speakers


Object Number: 1493963  Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Rear Speakers w/ Radio Amplifier
RR DEFOG, HORN, HI BLO MOT, RH BEC BATT, COOL FANS, and ABS Fuses
Power, Grounds, and Park Lamp Relay
Dimmer Switch
Data Link Connector (DLC) Schematics
SP202
SP203
Figure 2:

Rear Speakers with Radio Amplifier


Object Number: 778532  Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Rear Speakers w/o Radio Amplifier
Power and Front Speakers
BATT 1, PWR Seat, PWR Mirror, DR Lock, Trunk Release/RFA
SP401
Figure 3:

Rear Speakers without Radio Amplifier


Object Number: 778555  Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Rear Speakers w/ Radio Amplifier