Test Description

WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

Tests for other PASS-Key® DTCs stored in the BCM that will cause a DTC B2721 to set. These DTCs must be diagnosed first.
Tests for an intermittent or incorrect PASS-Key® Resister reading due to an incorrect or malfunctioning ignition key.

Fig 1: DTC B2721 (1 Of 2)
Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC B2721 (2 Of 2)

Courtesy of GENERAL MOTORS CORP.