Pass-Key(R) System

WARNING: This page is about a different car, the 2000 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

The PASS-Key(R) system is designed to prevent vehicle theft. If incorrect key is used, steering column is not unlocked and engine's fuel system and starter are disabled. An ignition key with a specific electrical resistance must be used in ignition key lock cylinder. PASS-Key(R) system operates using sensing contacts which are located in ignition key lock cylinder. These contact a key resistor pellet which is located on the ignition key. When lock is rotated, battery voltage is applied through appropriate fuse to BCM. Pellet resistance is then compared with programmed value in BCM non-volatile memory. There are 15 different resistances available. PASS-Key(R) system also disarms UTD system from armed or alarmed mode. If an invalid key is detected, system will disable fuel and cranking for 3 minutes. If a key is inserted or ignition switch is turned before 3 minutes has elapsed, timer will reset to 3 minutes. Disconnecting battery or removing fuses will not disable timer.

The BCM controls steering column lock/unlock function. Ground is supplied by BCM through ignition switch to prevent locking with key in ignition. BCM monitors lock position to assure lock command has been accomplished. If BCM is unable to determine lock position, BCM will enter fail enable mode and prevent column lock operation and fuel enable. To clear fail enable mode, disconnect BCM fuse No. 25 for 15 seconds.

System components include ignition key, ignition key lock cylinder, electronic steering column lock module, theft deterrent relay, BCM and PCM.