How To Register Secret Code

Each individual secret code is registered inside the transmitter, and so it is necessary to register these codes with the EEPROM inside the receiver in the following cases:

• When the transmitter or ETACS-ECU is replaced.
• If more transmitters are to be used.
• If it appears that a problem is occurring because of faulty registration of a code.

A maximum of 4 different codes can be stored in the EEPROM memory (4 different transmitters can be used). When the code for the first transmitter is registered, the previously registered codes for all transmitters are cleared. Therefore, if you are using 4 transmitters or adding more transmitters, the codes for all transmitters must be registered at the same time.

1. Check that the doors lock normally when the key is used.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to LOCK (OFF) position before connecting or disconnecting scan tool MB991502.
2. Insert the ignition key.
NOTE: This will connect terminal No. 1 of the data link connector to ground, and the system will be in secret code registration standby mode.
3. Connect the scan tool to the data link connector. If the scan tool is not used, ground terminal No. 1 of the data link connector.
NOTE: At this time the code registration monitor request is output (all doors locked and unlocked) and becomes registration mode.
4. Press the hazard switch 6 times within 10 seconds.
5. Press the transmitter switch, and then press it 2 times within 10 seconds of the first press. This will register the code.
6. When registration is completed, the code registration monitor request is output (all doors locked and unlocked).
7. If you are using 2 or more transmitters or have added a second transmitter, the same registration procedure should be carried out within one minute after registering the code for the first transmitter. After the second registration is completed, the code registration monitor request is output (all doors locked and unlocked).
8. Registration mode will be canceled under the following conditions:
   • When the secret code for 4 transmitters has been registered.
   • When one minute has been passed after registration mode started.
   • When scan tool MB991502 is disconnected (the ground connection is broken).
   • When the key is removed from the key cylinder.
9. After the registration is completed, carry out the following work, and then check that the keyless entry system operates normally.
   • Remove the ignition key.
   • Close all of the doors.