Immobilizer Control Unit

The immobilizer control unit is an electronic module in the instrument panel which verifies the validity of an ignition key when the ignition is turned ON.
To accomplish its purpose, the immobilizer control unit performs the following actions:
- Learns and stores the codes of valid keys.
- Reads the radio frequency input from the ignition key.
- Compares the received code with the codes of the valid keys.
- Sends a release message to the electronic control module (ECM) if a valid key has been presented.
- Calculates and transmits identification (ID) codes within each release message.
- Controls the external relay which interrupts the starter relay circuit.
- Controls the status indicator in the instrument cluster.
- Monitors system faults.
- Supports system test functions.