Encrypted Code Registration Method

Required Special Tool:
MB991502: Scan Tool (MUT-II)

CAUTION: Because registering the encrypted codes is done after all previously-registered codes have been erased, you should keep all of the ignition keys that have already been registered accessible.

If the ignition key, Immobilizer-ECU, ECM* or PCM* is replaced or an ignition key is added, encrypted codes of all the ignition keys must be registered. (A maximum of eight different ignition key can be registered.)

Moreover, when the immobilizer-ECU has been replaced, you will need to use scan tool MB991502 to register the immobilizer-ECU and input the vehicle secret code and to register the password (secret code) that the owner specifies into the immobilizer-ECU.

NOTE: *: If the ECM or PCM is replaced, the immobilizer-ECU and ignition key should be replaced together with it. Each ECM or PCM has an encrypted code for immobilizer-ECU, and the encrypted code is registered in the immobilizer-ECU and ignition key.

POINTS TO NOTE DURING OPERATION
1. If none of the functions can be used, check the diagnostic trouble codes, and after carrying out any necessary repairs, repeat the operation.
2. If an incorrect password is input five times in a row, the immobilizer-ECU judges that an unauthorized operation is being attempted. Start-prevention mode will be set, and engine operation will stop and all special functions will be disabled.
If the ignition switch is turned to "ON" position and left in that position for approximately 20 minutes, "Unauthorized operation, start-prevention mode" will be cancelled.

FUNCTION SELECTION

CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.

1. Connect scan tool MB991502 to data link connector (16 pin).
2. Turn the ignition switch to "ON" position.

3. This menu is displayed if "SPECIAL FUNCTION" is selected from the immobilizer function menu. Then perform the procedures by referring to "Key ID Register" and "Password Set."

NOTE: The functions displayed will vary depending on the vehicle model.

4. This completes the registration operation. Turn the ignition switch "LOCK" (OFF) and leave it off for approximately ten seconds.
5. Check that the engine can be started with each of the ignition keys.
6. Check that the immobilizer system DTC and MFI system DTC do not reset.
7. Turn the ignition switch to "LOCK" (OFF) position.
8. Disconnect scan tool MB991502.

Key ID Register

NOTE: Using the key ID register function will cause all key IDs that have been previously registered in the 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.

NOTE: If registering more than one key, do not disconnect scan tool MB991502 halfway through the registration process.

NOTE: After registering key IDs, check that the engine can be started using all of the keys that have been registered. If the engine will not start, refer to Immobilizer System Diagnosis.

1. Connect the MUT-II to DLC. Select Immobilizer, then select "SPECIAL FUNCTION." Select "key ID register."
2. Input the password.
Use the "UP" and "DOWN" keys to change the current password digit to a value between 0 and 9. Use the "LEFT" and "RIGHT" keys to move to a different password digit. Press the "YES" key to accept the password.

NOTE: Four separate digits must be input to make up the password.

3. If an incorrect password is input five times in a row, this screen is displayed and the immobilizer-ECU switches to "Unauthorized operation, start-prevention mode."

4. Insert the key to be registered into the ignition switch. Turn the ignition switch to the "ON" position. Press the "YES" key to start key ID registration.

5. This will be displayed when the key ID registration is successful.
If an error occurs during key ID registration, the message "Can't execute" will be displayed. If the key has already been registered, "Key ID has been registered" will be displayed.

6. The number of keys currently registered will be displayed. To register an additional key, replace the ignition key with the next key to be registered within five seconds and then press the "YES" key.
Press the "YES" key. Key ID registration screen will be displayed, then register another key.

NOTE: A maximum of eight different keys can be registered.

7. If key ID registration is complete, press the "NO" key.

Password Set

1. Enter the password.
Use the "UP" and "DOWN" keys to change the current password digit to a value between 0 and 9. Use the "LEFT" and "RIGHT" keys to move to a different password digit.
Press the "YES" key to accept the password.

NOTE: Four separate digits must be input to make up the password.

2. It an incorrect password is input five times in a row, this screen is displayed and the immobilizer-ECU switches to "Unauthorized operation, start-prevention mode."

3. Enter the new password.
The entering method is the same as that described in 1 above.

4. Press the "YES" key. The new password will then be registered.

5. This screen will be displayed once registration of the new password is complete.
If an error occurs during the resetting procedure, "Can't execute" is displayed.