Diagnostic Aids

WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections .
An open circuit, up to the first splice only from the BCM, will set the DTC.
A short to ground on the backup lamp supply voltage circuit, courtesy lamp supply voltage circuit OR the TBC 2B battery positive voltage circuit to the BCM will open the TBC 2B fuse in the left instrument panel fuse block.