2003 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Recognition Code Registration

WARNING: This page is about a different car, the 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. The vehicle should be in the following conditions:
    • The key is not inserted in the ignition key cylinder.
    • The driver's door is OPENED (the other doors are closed).
    • The driver's door is UNLOCKED.
  2. Perform the following after the above operations:
    1. Insert and remove the key from the ignition key cylinder twice within 5 seconds.
    2. After the above operation, close and open the driver door twice within 40 seconds. Then insert the key into the ignition key cylinder and remove it.
    3. After the above operations, close and open the driver door twice within 40 seconds. Then insert the key into the ignition key cylinder and close the door.
    4. Turn the ignition switch from LOCK to ON and back to LOCK at approximately 1 second interval 1-5 times to select the mode. See Fig 1. Then remove the key from the ignition key cylinder.
    5. Multiplex communication system (MPX) body ECU automatically performs the LOCK-UNLOCK operation within 3 seconds to inform the operator of a selected mode. See Fig 2.
  3. Register transmitter:
    1. Within 40 seconds after the add mode or the rewrite mode has been selected, press the LOCK and UNLOCK switches on the transmitter switch simultaneously for 1.0-1.5 seconds.
    2. Within 3 seconds after the above operation, press either one of the switches for more than 1 second.
    3. Within 3 seconds after the transmitter switch has been turned OFF, the LOCK-UNLOCK operation will be automatically performed once if the registration of the recognition code of the transmitter is completely correctly. See Fig 3. In case the LOCK-UNLOCK operation is performed twice, the registration of recognition code has failed. Perform the registration procedure from the beginning once again.
    4. When continuing the registration, register the transmitter within 40 seconds after the previous registration.
    4. NOTE: Four types of recognition codes can be registered at one time.
  4. If even one of the following conditions is satisfied, registration of recognition codes is completed:
    • Forty seconds have elapsed since the door control relay responds.
    • The driver's door is opened.
    • The key plate is inserted in the ignition key cylinder.
    • Four types of recognition codes are registered at one time.
Fig 1: Identifying ON-LOCK Operation Mode
G00176299Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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