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Diagnosis Procedure

WARNING: This page is about a different car, the 2008 Nissan Titan. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK HARNESS BETWEEN BLUETOOTH CONTROL UNIT AND MICROPHONE
    1. Turn ignition switch OFF.
    2. Disconnect Bluetooth control unit connector and microphone connector.
    3. Check continuity between Bluetooth control unit harness connector B142 (A) and microphone harness connector R109 (B).
      CONTINUITY CHART

      A B Continuity
      Connector Terminal Connector Terminal
      B142 7 R109 1 Yes
      8 2
      29 4
    4. Check continuity between Bluetooth control unit harness connector B142 (A) and ground.
    CONNECTOR TERMINAL CONTINUITY CHART

    A - Continuity
    Connector Terminal
    B142 7 Ground No
    8
    29
    Fig 1: Checking Continuity Between Bluetooth Control Unit Harness Connector B142 And Ground
    G04889899Courtesy of NISSAN MOTOR CO., U.S.A.

    Are the continuity test results as specified? 

    Yes: GO TO  2

    No: Repair harness or connector.

  2. CHECK MICROPHONE POWER SUPPLY
    1. Connect Bluetooth control unit connector and microphone connector.
    2. Turn ignition switch ON.
    3. Check voltage between microphone harness connector R109 terminal 4 and ground.

    4 - Ground : Approx. 5V 

    Fig 2: Checking Voltage Between Microphone Harness Connector R109 Terminal 4 And Ground
    G04889900Courtesy of NISSAN MOTOR CO., U.S.A.

    Is voltage reading approx. 5 volts? 

    Yes: GO TO  3

    No: Replace Bluetooth control unit. Refer to , "REMOVAL AND INSTALLATION ".

  3. CHECK MICROPHONE SIGNAL

    Check signal between Bluetooth control unit harness connector B142 terminals 7 and 8 with CONSULT-III or and oscilloscope.

    CONNECTOR TERMINAL SIGNAL CHART

    Connector (+) (-) Reference signal
    Terminal Terminal
    B142 7 8 While speaking into MIC
    G05708296Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 3: Checking Signal Between Bluetooth Control Unit Harness Connector B142 Terminals 7 And 8
    G05708297Courtesy of NISSAN MOTOR CO., U.S.A.

    Are voltage readings as specified? 

    Yes: Replace Bluetooth control unit. Refer to , "REMOVAL AND INSTALLATION ".

    No: Replace microphone. Refer to , "REMOVAL AND INSTALLATION ".

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