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Mute Signal Circuit between Navigation Receiver Assembly and Multi-media Interface ECU: Procedure

  1. INSPECT MULTI-MEDIA INTERFACE ECU 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 1: Identifying Multi-Media Interface ECU
      GTY296390Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      E30-6 (MUT1) - Body ground Ignition switch ACC, USB audio system or satellite radio playing → Changing sources Above 3.5 V → Below 1 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Multi-media Interface ECU)

    NG → See step   2 

    OK → See step   4 

  2. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - MULTI-MEDIA INTERFACE ECU) 
    1. Disconnect the E15 navigation receiver assembly connector.
    2. Disconnect the E30 multi-media interface ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E15-6 (MUTE) - E30-6 (MUT1) Always Below 1 Ω
      E15-6 (MUTE) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. REPLACE MULTI-MEDIA INTERFACE ECU 
    1. Replace the multi-media interface ECU and check that the malfunction disappears. Refer to REMOVAL .

      OK

      Malfunction disappears.

    NG → See step   5 

    OK → END 

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