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Automatic Key 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. Registration of a new transponder key must be done when you install a new ECM.
    • The new ECM is in the automatic key code registration mode. The number of key codes for this ECM is already fixed, and so it can be registered. On this type of vehicle, up to 3 key codes can be registered. In the automatic registration mode, the key registered last becomes the sub-key.
    • For new transponder key registration steps, refer to flowchart. See Fig 1.
    • When no key is inserted in the key cylinder in the automatic registration mode, the security indicator always lights up. When the immobilizer system operates normally and the key is pulled out, the security indicator blinks. See Fig 2. When the key code registration could not be performed in the automatic registration mode, code 2-1 is output from the security indicator. When inserting an already registered key, code 2-2 is output.
  2. Perform the automatic registration mode completion if finishing the mode forcibly after registering more than 1 key codes in the automatic registration mode. After 1 more key code has been registered with the master key, perform one of the following steps without pulling the key out or inserting the already registered key.
    • Depress and release the brake pedal 5 times or more within 15 seconds.
    • With the hand-held tester, require the automatic registration mode completion.
Fig 1: Automatic Key Registration Flowchart
G00173765Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Identifying Automatic Key Registration Normal & Abnormal Operation
G00173766Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002