Diagnostic Aids

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Use a scan tool in order to inspect the Passlock™ data voltage and the Passlock™ code.
Inspect the Passlock™ sensor harness for an intermittent or a short to ground. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Following a repair the tamper timer needs 10 minutes in order to expire.