No. 3 Transmitter Id Code Cannot Be Reprogrammed: Notes

WARNING: This page is about a different car, the 2007 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

TRANSMITTER ID CODE CANNOT BE REPROGRAMMED POSSIBLE CAUSES

3	Transmitter ID code cannot be reprogrammed
DESCRIPTION	Malfunction in transmitter battery, transmitter, keyless receive bracket, keyless receive bracket ground screw, or keyless control module circuit, keyless receive circuit.
POSSIBLE CAUSE	Malfunction in transmitter battery, transmitter, keyless receive bracket, keyless receive bracket ground screw, or keyless control module, or keyless receive.