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Immobilizer Function




GENERAL INFORMATION

IMMOBILIZER FUNCTION

CONSTRUCTION DIAGRAM





OPERATION

1. When the ignition key is inserted to the ignition switch and the ignition switch is turned to the ON position, WCM transmits an ID code (key ID) registered in the WCM to the ignition key via the steering lock (key reminder switch) by radio.
2. When the ignition key receives the transmission signal from WCM, the transponder (small transmitter) integrated in the ignition key transmits an ID code peculiar to each key (key ID) to WCM via the steering lock (key reminder switch) by radio.
3. WCM compares the ID code (key ID) sent from the ignition key with the already-registered ID code (key ID), and only when they match, the starting of engine is permitted.
4. More than one trillion of ID code (key ID) combinations can be registered, and this feature prevents code copying, resulting in higher security of the system.
NOTE:

- The transponder integrated in the ignition key uses the power supplied from WCM. Therefore, it can be used even when the battery in ignition key (for transmitter) is discharged.
- Two ignition keys (transmitter and transponder) are provided, and up to eight keys can be registered to one vehicle as needed.
- When WCM is replaced or when the key is lost or added, the ID codes for all the keys (key ID) must be registered using M.U.T.-III.