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 that has been sent previously.
  4. This prevents anyone from recording and playing back the signal from the transmitter.

  5. Resynchronization may be necessary in the following circumstances:
  6. • The battery in the transmitter is very weak.
    • The battery in the transmitter is replaced.
    • The battery in the vehicle has been in a low or no charge condition for an extended period of time.
  7. In order to resynchronize the transmitter with the receiver, perform the following steps:
  8. 4.1. Stand within 1.5 meters (5 ft) from the vehicle.
    4.2. Simultaneously press and hold the LOCK and UNLOCK buttons on the transmitter for 7 seconds.

    The door locks should cycle in order to confirm resynchronization.