Immobilizer interface module is used when installing remote start products in vehicles equipped with an RF based immobilizer system. This type of system uses a small chip imbedded in the ignition key, called a transponder, to transmit a very low powered RF signal. This signal is picked up through an antenna (or coil) around the ignition switch which is then sent to the Immobilizer’s transceiver. Once the correct signal is received, the Immobilizer will enable the ignition and/or fuel system. The KEYBOX bypasses the immobilizer system only while the remote start is in use, maintaining the factory system’s integrity. When the remote start system is not in use the factory immobilizer remains fully functional.