Diagnostic Aids

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Short to ground or an open/high resistance will also set multiple history no communication codes for GMLAN high speed modules
Module terminal tension should be checked before any module is replaced.