GM Service Manual Online
For 1990-2009 cars only
  1. Resynchronization may be necessary due to the security method used by the RKE system.
  2. The transmitter does not send the same signal twice to the receiver.

  3. The receiver will not respond to a signal which has been previously sent. This prevents anyone from recording and playing back the signal from the transmitter.
  4. Resynchronization will be necessary if any of the following are true:
  5. • You change the transmitter battery.
    • You disconnect the vehicle battery.
    • You push the transmitter button 256 times out of the range of the receiver.
  6. In order to resynchronize the transmitter with the receiver, perform the following steps:
  7. 4.1. Stand close to the vehicle.
    4.2. Simultaneously press and hold the LOCK and UNLOCK buttons on the transmitter for seven seconds.

    The door locks should cycle to confirm resynchronization.