GM Service Manual Online
For 1990-2009 cars only

Important: 

   • Any new BCM will automatically program to the resistance of the ignition key being used at the first ignition ON cycle. This can only be done once for the life of the module.
   • The BCM can only be programmed to one ignition key resistance. All ignition key resistances must match.

A new BCM is not programmed. Before the system will function properly it must be programmed to the code that matches the customer's keys.

  1. Insert one of the customer's keys into the ignition cylinder and turn it to the ON position. Start the engine at this time in order to verify system operation.
  2. Observe the SECURITY indicator lamp for the following conditions:
  3. • The indicator lamp lights steadily for approximately 5 seconds and then goes out. This indicates that the BCM is programmed properly.
    • The indicator lamp flashes at a rate of one flash per second until the ignition is turned OFF. This indicates that the BCM did not program and the system should be checked for a fault. Refer to Diagnostic System Check - Theft Deterrent in Theft Deterrent.

Important: After programming, perform the following to avoid future misdiagnosis:

  1. Turn the ignition OFF for 10 seconds.
  2. Connect the scan tool to the data link connector.
  3. Turn the ignition ON with the engine OFF.
  4. Use the scan tool in order to retrieve history DTCs from all modules.
  5. Clear all history DTCs.