Information related immobilizer,that are classified as 2(two) parts independently, is memorized in EEPROM. ECM check these 2(two) information berfore proceeding immobilizer authentication. With synchronized both information, ECM starts immobilizer authentication procedure. If both information is not synchronized, ECM stops immobilizer authentication, Limphome function will not be activated, and memorizes DTC P1695. If DTC P1695 is retrieved again, after performing new key teaching procedure, ECM should be replaced with new one.

If key/password information in ECM is not matching or there is write error on EEPROM as hardware, DTC P1696 is set.

Fig.1) It shows that ECU is learnt status.