Diagnostic Aids

WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Use the scan tool in order to inspect the Passlock data voltage and the Passlock code.
Inspect the Passlock sensor harness at the Passlock sensor and the lower steering column connector for an intermittent, short to ground or short to battery. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems.
Following a repair the tamper timer may need 10 minutes in order to expire.
You may be directed to this table from the VTD Diagnostic System Check without a DTC B2955 being set. If you were directed to this table, follow all of the steps in this diagnostic table.
When directed to this table DTC B2955 may have a history status.
The VTD internal diagnostics are not run while the tamper timer is active.
Prior to replacing a BCM, ensure that all of the diagnostics have been completed. Refer to diagnostic trouble code list.