The transmitter code will go out of synchronization if any button of a 4 button transmitter is pressed more than 250 times outside the range of the receiver which is inside the BCM. In other words the transmitter will not work. To synchronize the code of the particular transmitter with the receiver, press and hold both lock and decklid release buttons simultaneously for 5 seconds. Release the buttons and wait until the doors unlock indicating that the code has been synchronized. This may require waiting for as long as 6 minutes.