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Audio Communication Line Check (Between Display Control Unit and Audio Unit)

WARNING: This page is about a different car, the 2003 Nissan Murano. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK POWER SUPPLY AND GROUND CIRCUIT 
    1. Check system of power supply and ground circuit audio unit. Refer to POWER DISTRIBUTION .

    OK or NG

    1. OK : GO TO 2.
    2. NG : Check the malfunctioning parts.
  2. CHECK HARNESS 
    1. Turn ignition switch OFF.
    2. Disconnect audio unit connector and display control unit connector.
    3. Check continuity between audio unit and display control unit.
      AUDIO UNIT COMMUNICATION LINE HARNESS CHECK (1 OF 2)

      Terminals Continuity
      Display control unit (+) Audio unit (-)
      Connector Terminal (Wire color) Connector Terminal (Wire color)
      M43 40 (R/G) M46 23 (R/G) Yes
      42 (R/Y) 21 (R/Y)
    4. Check continuity between display control unit and ground.
      Fig 1: Checking Continuity Between Audio Unit And Display Control Unit, And Between Display Control Unit And Ground
      G03360107Courtesy of NISSAN MOTOR CO., U.S.A.
    AUDIO UNIT COMMUNICATION LINE HARNESS CHECK (2 OF 2)

    Terminals Continuity
    Display control unit (+) (-)
    Connector Terminal (Wire color)
    M43 40 (R/G) Ground No
    42 (R/Y)

    OK or NG

    1. OK : GO TO 3.
    2. NG : Repair harness or connector.
  3. CHECK1: AUDIO-TX COMMUNICATION SIGNAL 
    1. Connect display control unit connector.
    2. Turn ignition switch ON.
    3. Check voltage between display control unit harness connector M43 terminal 40 (R/G) and ground.
      1. Approx. 3.5 V or more 

    OK or NG

    1. OK : GO TO 4.
    2. NG : Replace display control unit.
    Fig 2: Checking Voltage Between Display Control Unit Harness Connector M43 Terminal 40 And Ground
    G03360108Courtesy of NISSAN MOTOR CO., U.S.A.
  4. CHECK2: AUDIO-RX COMMUNICATION SIGNAL 
    1. Connect audio unit connector.
    2. Turn ignition switch ON.
    3. Check voltage between display control unit harness connector M43 terminal 42 (R/Y) and ground.
      1. Approx. 3.5 V or more 

    OK or NG

    1. OK : GO TO 5.
    2. NG : Replace audio unit.
    Fig 3: Checking Voltage Between Display Control Unit Harness Connector M43 Terminal 42 And Ground
    G03360109Courtesy of NISSAN MOTOR CO., U.S.A.
  5. CHECK3: AUDIO-TX COMMUNICATION SIGNAL 
    1. Turn ignition switch ON.
    2. Check signal between display control unit harness connector M43 terminal 40 (R/G) and ground with CONSULT-II or oscilloscope.
      1. 40 (R/G) - Ground : Refer to " TERMINALS AND REFERENCE VALUE FOR DISPLAY CONTROL UNIT   ".  

    OK or NG

    1. OK : GO TO 6.
    2. NG : Replace audio unit.
    Fig 4: Checking Voltage Between Display Control Unit Harness Connector M43 Terminal 40 And Ground
    G03360110Courtesy of NISSAN MOTOR CO., U.S.A.
  6. CHECK4: AUDIO-RX COMMUNICATION SIGNAL 
    1. Turn ignition switch ON.
    2. Check signal between display control unit harness connector M43 terminal 42 (R/Y) and ground with CONSULT-II or oscilloscope.
      1. 42 (R/Y) - Ground : Refer to " TERMINALS AND REFERENCE VALUE FOR DISPLAY CONTROL UNIT   ".  

    OK or NG

    1. OK : Replace audio unit.
    2. NG : Replace display control unit.
    Fig 5: Checking Voltage Between Display Control Unit Harness Connector M43 Terminal 42 And Ground
    G03360111Courtesy of NISSAN MOTOR CO., U.S.A.
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