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Home >> Infiniti >> 2011 >> M37 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 10 (Audio, Visual & Navigation System) >> DTC/Circuit Diagnosis >> Mode Change Signal Circuit >> Diagnosis Procedure
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Diagnosis Procedure

WARNING: This page is about a different car, the 2011 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK CONTINUITY MODE CHANGE SIGNAL CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect BOSE amp. connector and AV control unit connector.
    3. Check continuity between BOSE amp. harness connector and AV control unit harness connector.
      CONTINUITY SPECIFICATION

      AV control unit BOSE amp. Continuity
      Connector Terminal Connector Terminal
      M209 30 B230 37 Existed
    4. Check continuity between BOSE amp. harness connector and ground.
      CONTINUITY SPECIFICATION

      BOSE amp. Ground Continuity
      Connector Terminal
      B230 37 Not existed

      Is the inspection result normal? 

      YES: Go to 2.

      NO: Repair harness or connector.

  2. CHECK MODE CHANGE SIGNAL
    1. Connect BOSE amp. connector and AV control unit connector.
    2. Turn ignition switch ON.
    3. Check voltage between BOSE amp. harness connector and ground.
      VOLTAGE SPECIFICATION

      (+) (-) Condition Voltage (Approx.)
      BOSE amp.
      Connector Terminal
      B230 37 Ground Driver's Audio Stage ON. 0 V
      Driver's Audio Stage OFF. 8.5 V

      Is the inspection result normal? 

      YES: Replace BOSE amp. Refer to "REMOVAL AND INSTALLATION ".

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