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

Antenna, DLC, Ground, Power, and User Inputs


Object Number: 1583424  Size: FS
Master Electrical Component List
OnStar Description and Operation
Control Module References
Audio Output
B+ Bus Bar - 2 of 2
High Speed GMLAN
G305 (1 of 2)
G301, G102, G303, and G402
Figure 2:

Audio Output


Object Number: 1583425  Size: FS
Master Electrical Component List
OnStar Description and Operation
Control Module References
Antenna, DLC, Ground, Power, and User Inputs