For 1990-2009 cars

Note: To confirm if the vehicle has an immobilizer system, please check the vehicle SPID label or the VIN in GMVIS for the presence of RPO BAH (engine immobilizer).

Note: Turn ON the ignition before installing in the scan tool. Failure to connect in this procedure may cause communication errors and the programming procedure will not complete. Any keys that are not programmed at this time will no longer function.

Note: Try to obtain all the keys. At least 2 keys are necessary to successfully program the immobilizer system.

A maximum of 5 keys may be programmed.

### Conditions

Use these procedures after replacing:

• | Theft deterrent control module (Immobilizer)

• | Engine control module (ECM)

• | Any key

### Immobilizer Programming Procedure

1. Turn the ignition switch to the ON position.
2. Install the scan tool.
3. Select IMMOBILIZER PROGRAMMING FUNCTION from the BODY menu.
4. Follow the scan tool instructions with each key until all keys are programmed.
5. Turn the ignition to the LOCK position, disconnect the scan tool and test all the keys.
6. If any key does not function, perform this procedure again with all keys.
7. If any key does not accept the programming, replace it with a new key and perform this procedure again with all the keys.