2003 Chevrolet Cavalier Owner's Manual - Page 76

Resynchronization Your remote keyless entry system is equipped with a security system that prevents anyone from recording and playing back your signal. The transmitter does not send the same signal twice to the receiver. The receiver will not respond to a signal that has been sent to it more than once. Normally, the transmitter and receiver resynchronize automatically. However, under certain circumstances, manual resynchronization may be required. To resynchronize your transmitter and receiver, follow these directions: 1. Stand close to your vehicle. 2. Press and hold the LOCK and UNLOCK buttons on the transmitter at the same time. 3. Hold the buttons for at least 10 seconds. During this time, the doors should lock and unlock once. This confirms the resynchronization. If the doors do not lock and unlock, see your dealer for service. 2-7