The engine immobilizer system consists of an Electronic Control Module (ECM), transponder key coil, transponder key amplifier and key with built-in transponder chip. See Fig. 1. When ignition key is inserted in ignition, the transponder chip in the key transmits an electronic code to the transponder key coil. The signal is amplified, and read by the ECM. The engine will start only when the key code is the same as the code registered in the ECM. System is reset each time key is removed from ignition switch.