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Home >> Infiniti >> 2012 >> G25 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 13 (Audio, Visual, Navigation System) >> [Base Audio & Navigation] >> DTC/Circuit Diagnosis >> Microphone Signal Circuit >> Diagnosis Procedure
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Diagnosis Procedure

WARNING: This page is about a different car, the 2011 Nissan Leaf. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK HARNESS CONTINUITY BETWEEN AV CONTROL UNIT AND MICROPHONE
    1. Turn the ignition switch OFF.
    2. Disconnect the AV control unit and microphone connectors.
    3. Check for continuity between the AV control unit harness connector and microphone harness connector.
      CONTINUITY REFERENCE CHART

      AV control unit Microphone Continuity
      Connector Terminal Connector Terminal
      M84 46 R3 1 Exists
      47 4
      48 2
    4. Check for continuity between the AV control unit harness connector and ground.
      CONTINUITY REFERENCE CHART

      AV control unit Ground Continuity
      Connector Terminal
      M84 46 Does not exist
      47

      Is the check result normal? 

      YES: GO TO 2.

      NO: Repair the harnesses or connectors.

  2. CHECK MICROPHONE POWER SUPPLY VOLTAGE
    1. Connect the AV control unit connector.
    2. Turn power switch ON.
    3. Check voltage between AV control unit harness connectors.
      VOLTAGE REFERENCE CHART

      Probe Standard Reference value
      (+) (-)
      AV control unit
      Connector Terminal Connector Terminal
      M84 47 M84 48 4.7 - 5.3 V Approximately 5 V

      Is the check result normal? 

      YES: GO TO 3.

      NO: Replace the AV control unit. Refer to "REMOVAL AND INSTALLATION ".

  3. CHECK MICROPHONE SIGNAL
    1. Turn the ignition switch OFF.
    2. Connect the microphone connector.
    3. Turn power switch ON.
    4. Check signals between the AV control unit harness connector terminals.
      SIGNALS REFERENCE CHART

      Probe Test condition Standard Reference value
      (+) (-)
      AV control unit
      Connector Terminal Connector Terminal
      M84 46 M84 48 Microphone sound input The value between the maximum input voltage and the minimum input voltage is 4.72 V or less.
      G07088405Courtesy of NISSAN MOTOR CO., U.S.A.

      Is the check result normal? 

      YES: Replace the AV control unit. Refer to "REMOVAL AND INSTALLATION ".

      NO: Replace the microphone. Refer to "REMOVAL AND INSTALLATION ".