GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Radio/Navigation System Schematics
Figure 1:

Radio
Object Number: 1842321 Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Control Module References
Radio/Navigation System Schematics - Speakers
RDO/CHIME, CHMSL, and PWR POST Fuses/Circuit Breakers
RDO/CHIME, CHMSL, and PWR POST Fuses/Circuit Breakers
G103 - 1 of 2, G105, and G106
Interior Lights Dimming Schematics
Splice Pack SP203
Figure 2:

Speakers
Object Number: 1842343 Size: FS
Master Electrical Component List
Radio/Audio System Description and Operation
Control Module References
Radio/Navigation System Schematics - Radio