Conditions for Setting the DTC

WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

C0800 03

During initialization or when the system is inactive, the system voltage is less than 10.5 volts.
During the system operation, the system voltage is less than 9.5 volts.

C0800 07

Ignition is in RUN.
The system voltage is greater than 17 volts.