Diagnostic Aids
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
The ignition may need to be cycled twice, waiting 30 seconds between key cycles, to move the code from current to history
If there are any other DTCs set for GMLAN communication such as U0100, U0121, U0140, or U2099, diagnose them first before resolving DTCs described in this section.