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Multi-media Interface ECU Power Source Circuit: Procedure

  1. INSPECT MULTI-MEDIA INTERFACE ECU 
    1. Disconnect the multi-media interface ECU connector.
    2. Measure the voltage according to the value(s) in the table below.
      Fig 1: Identifying Multi-Media Interface ECU Connector
      GTY350427Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      U9-12 (+B) - U9-7 (GND) Always 11 to 14 V
      U9-11 (ACC) - U9-7 (GND) Engine switch on (ACC) 11 to 14 V

    NG → See step   2 

    OK → See step   3 

  2. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the radio receiver assembly connector.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 2: Radio Receiver Assembly Connector
      GTY359088Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      U9-11 (ACC) - G11-11 (ACC) Always Below 1 Ω
      U9-12 (+B) - G11-12 (+B) Always Below 1 Ω
      U9-7 (GND) - G11-7 (GND) Always Below 1 Ω
      U9-11 (ACC) - Body ground Always 10 kΩ or higher
      U9-12 (B+) - Body ground Always 10 kΩ or higher
      U9-7 (GND) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Multi-media Interface ECU)
      *2 Front view of wire harness connector
      (to Radio Receiver Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   3 

  3. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE