Radio/Audio System Schematics (UQ7 W/Y91)
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Radio/Audio System Schematics (UQ7 W/ Y91) (Power, Ground, Low Level Audio Signals-UQ7 W/Y91)
Fig 4: Radio/Audio System Schematics (UQ7 W/ Y91) (Amplifier, RSA Power, Ground, Subsystems-UQ7 W/Y91)