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

Power and Ground


Object Number: 876698  Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Radio to Speakers (w/o U85)
IGN MAIN 2, RADIO, SUNROOF, STR WHL CTRL, WIPER, MALL, MALL PGM Fuses, and PWR WDO Circuit Breaker
BATT MAIN 2, R DEFOG, H SEAT/LUM, PWR LOCK, RADIO AMP Fuses and SEAT Circuit Breaker
IGN MAIN 2, RADIO, SUNROOF, STR WHL CTRL, WIPER, MALL, MALL PGM Fuses, and PWR WDO Circuit Breaker
Steering Wheel Controls
DLC
Vehicle Interface Unit (VIU) to On-Star Keypad and Radio
Headlamp Switch and Instrument Panel Lighting
G201
Figure 2:

Radio to Speakers (w/o U85)


Object Number: 876699  Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Radio to Amplifier (w/U85)
Power and Ground
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Figure 3:

Radio to Amplifier (U85)


Object Number: 770507  Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Amplifier to Speakers (w/U85)
Radio to Speakers (w/o U85)
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Entertainment Schematic Icons
Figure 4:

Amplifier to Speakers (U85)


Object Number: 876703  Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Radio to Amplifier (w/U85)
Entertainment Schematic Icons
Entertainment Schematic Icons