Encrypted Code Registration Method (Immobilizer): Notes
NOTE:
If PCM is replaced, immobilizer-ECU should also be replaced. PCM has an encrypted code for immobilizer-ECU, and encrypted code is registered in immobilizer-ECU and ignition key.
NOTE:
Using key ID register function will cause all key ID's that have been previously registered in immobilizer-ECU to be erased. All keys need to be registered. Those which have been registered before should be on hand before using this function. If registering more than one key, do not disconnect scan tool halfway through the registration process. After registering key IDs, check that engine can be started using all keys that have been registered. If engine will not start, see DIFFICULT TO START/NO START (CRANKS OKAY) in TESTING - NO CODES article.
If Immobilizer-ECU or PCM is replaced, or an ignition key is added encrypted codes of all ignition keys must be registered. (A maximum of eight different ignition key can be registered.) When the immobilizer-ECU has been replaced, scan tool MB991502 (MUT-II) must be used to register immobilizer-ECU and input vehicle secret code and register password (secret code) that owner specifies into immobilizer-ECU. If an attempt is made to start the engine with an unregistered ignition key, cranking occurs, but fuel supply is cut off disabling engine. After about 10 seconds, theft-alarm indicator in instrument cluster will blink for about 30 seconds.