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Section 427 (Key Reminder Warning System - Diagnostics): Pre-Check

WARNING: This page is about a different car, the 2003 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
  1. Using Hand-Held Tester 
    1. Hook up hand-held tester to the DLC3.
    2. Monitor the ECU data by following the prompts on the tester screen.
    NOTE:

    The hand-held tester has a "Snapshot" function which records the monitored data.

    Refer to the hand-held tester operator's manual for further details.

  2. Data List 
    NOTE: According to the DATA LIST displayed by the hand-held tester, you can read the value of the switch, sensor, actuator and so on without parts removal. Reading the DATA LIST as a first step of troubleshooting is one of the method to shorten the labor time.
    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch ON.
    3. According to the display on tester, read the DATA LIST.

      Standard (Body ECU): 

      BODY ECU DATA LIST

      Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
      KEY UNLK WRN SW Key unlock warning SW signal/ ON or OFF ON: Key is in IG key cylinder OFF: No key is in IG key cylinder -
      D DOOR CTY SW Driver's door courtesy SW signal/ ON or OFF ON: Driver's door is open OFF: Driver's door is closed -