Immobilizer System Description
The purpose of the IMMO system is to provide and additional anti-theft to the vehicle which is installed in, preventing it from an unauthorized use. Checking of user authorization is done by use of an ignition key whose head integrates a crypto-transponder. The Described system is a transponder-based immobilizer for an automotive vehicle.
The products constituting the application are the following ones:
- Up to 4 ignition keys with transponder integrated in the key head.
- The antenna (toroidal coil) for energizing and communicate with the transponder with its integrated electronic modulator/demodulator driver.
- The ISU control unit (Intelligent Switching Unit), in which Immobilizer function is managed.
- The ECM control unit (Engine Control Management).
- The external status indicator (LED) for displaying the Immobilizer status.
- The serial data link between ISU and EMS control unit.
- The data link and supply link between ISU control unit and antenna Plus the standard components, conforming to Diagnostic standard Keyword Protocol 2000:
- The Diagnostic Tester.
- The serial data link (K line) between Tester and vehicle ECM (Engine Control Module).
Only Immobilizer related requirements of the ISU control unit and ECM control unit are described in this article.