A transponder Key is A key that has a chip inside that transmits and receives data. These devices contain one of over a trillion unique codes. When the key is inserted into the ignition, the transponder sends a signal, If the signal is recognized by the immobilizer of the vehicle, then the engine will start. If the signal is not recognized or has been weakened by damage to the transponder then the immobilizer will shut down vital operating systems to the engine and it will not run. This technology greatly reduces the risk of car theft and provides peace of mind for the owner of the vehicle.