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Home >> Infiniti >> 2024 >> QX55 Essential >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> Audio, Visual & Navigation System (DTC/Circuit Diagnosis) >> DTC/Circuit Diagnosis >> Multi Av (Av Control Unit) >> B1309 Av Control Unit >> DTC Diagnosis Procedure
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DTC Diagnosis Procedure

  1. DETERMINE MALFUNCTION TYPE 
    1. SYMBOL CONSULT
      1. Ignition switch ON.
      2. Ignition switch OFF and wait at least 30 seconds.
      3. Ignition switch ON and wait at least 30 seconds or more.
      4. Select "Self Diagnostic Result" mode of "MULTI AV".
      5. Check DTC.

    Is DTC B1309-11 or 12 detected?

    YES>>

    11 [GND-SHORT] - GO TO 2.

    YES>>

    12 [VB-SHOR] - GO TO 3.

    NO>>

    Refer to Intermittent Incident .

  2. CHECK AV COMMUNICATION CIRCUIT FOR SHORT TO GROUND 
      1. Ignition switch OFF.
      2. Disconnect AV control unit connector, combination meter connector, head up display unit connector (if equipped), integral switch connector and Bose speaker amp. connector (if equipped).
      3. Check the continuity between AV control unit connector and ground.
        AV control unit   Continuity
        Connector Terminal Ground
        M139 38 - No
        39
        58
        59

    Is the inspection result normal?

    YES>>

    Replace AV control unit. Refer to Removal and Installation .

    NO>>

    Repair or replace harness or connectors.

  3. CHECK AV COMMUNICATION CIRCUIT FOR SHORT TO POWER SUPPLY 
      1. Ignition switch OFF.
      2. Disconnect AV control unit connector, combination meter connector, head up display unit connector (if equipped), integral switch connector and Bose speaker amp. connector (if equipped).
      3. Ignition switch ON.
      4. Check the voltage between AV control unit connector and ground.
        AV control unit Ground Voltage(Approx.)
        Connector Terminal
        M139 38 - 0 V
        39
        58
        59

    Is the inspection result normal?

    YES>>

    Replace AV control unit. Refer to Removal and Installation .

    NO>>

    Repair or replace harness or connectors.