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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.
      1. If the microphone function is normal, proceed to A.
      2. If the microphone function is malfunctioning, proceed to B.

    B:  GO TO NAVIGATION SYSTEM

    A: GO TO Next Step 

  2. CHECK WIRE HARNESS (MAYDAY ECU - MAP LIGHT) 
    1. Disconnect the U45 ECU connector.
    2. Disconnect the W6 map light connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      U45-7 (MCVD) - W6-19 (ACC) Below 1 Ω
      U45-7 (MCVD) or W6-19 (ACC) - Body ground 10 kΩ or higher
      Fig 1: Identifying U45 ECU And W6 Map Light Connector Terminals
      G05314866Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: GO TO Next Step 

  3. CHECK WIRE HARNESS (MAP LIGHT - BODY GROUND) 
    1. Disconnect the W6 map light connector.
    2. Measure the resistance of the wire harness side connector.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      W6-31 (GND3) - Body ground Below 1 Ω
      Fig 2: Identifying W6 Map Light Connector Terminals
      G05300057Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: GO TO Next Step 

  4. CHECK OPERATION OF MAP LIGHT ASSEMBLY 
    1. Temporarily replace the map light with a new or normally functioning one.
    2. Check that the 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)