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Inspection Procedure

  1. CHECK NAVIGATION SYSTEM 
    1. Start the navigation system and check that the voice recognition microphone function operates normally.

      Result 

      RESULT CHART

      Result Proceed to
      Microphone function is normal A
      Microphone function is malfunctioning (for DVD) B
      Microphone function is malfunctioning (for HDD) C

      B: GO TO NAVIGATION SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

      C: GO TO NAVIGATION SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

      A: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (MAYDAY ECU - MAP LIGHT) 
    1. Disconnect the R24 ECU connector.
    2. Disconnect the X4 map light connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R24-7 (TACC) - X4-22 (ACC) Always Below 1 Ω
      R24-7 (TACC) or X4-22 (ACC) - Body ground Always 10 kΩ or higher
      Fig 1: Identifying R24 ECU And X4 Map Light Connector Terminals
      G04945807Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR THEN CLEAR HISTORIC DTC 

      OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (MAP LIGHT - BODY GROUND) 
    1. Disconnect the X4 map light connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      X4-1 (GND) - Body ground Always Below 1 Ω
      Fig 2: Identifying X4 Map Light Connector Terminals
      G05784482Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR THEN CLEAR HISTORIC DTC 

      OK: Go to Next Step 

  4. CHECK MAP LIGHT ASSEMBLY (OPERATION) 
    1. Temporarily replace the map light with a new or normally functioning one for standard body (see REMOVAL ) or long body (see REMOVAL ).
    2. Check that DTC 4-3 is output.

      OK: DTC 4-3 is not output. 

      NG: REPLACE MAYDAY ECU TOGETHER WITH MAYDAY BATTERY AND THEN PERFORM REGISTRATION 

      OK: END (MAP LIGHT IS FAULTY; CLEAR HISTORIC DTC)