Diagnostic Aids

WARNING: This page is about a different car, the 2002 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.

If there is an open or short in any of the Passlock™ sensor circuits, the BCM will be unable to read a valid code from the Passlock™ sensor when the program mode is active.
Always diagnose all other Passlock™ DTCs first before diagnosing this DTC. These DTCs will affect the BCM's ability to properly read a Passlock™ code.
If DTC B3031 is set in the BCM as a history DTC, clear the DTC and recheck the system. A history DTC B3031 indicates that the BCM has successfully completed the programming mode.