AUDIO AND VISUAL SYSTEM AVC-LAN Circuit

DESCRIPTION

Each audio system component connected to the AVC-LAN (communication bus) transfers switch signals using the audio visual communication local area network.

If a short to +B or short to ground occurs in the AVC-LAN, the audio system will not function normally because communication is not possible.

WIRING DIAGRAM

A01WT54E11
*1 Parking Assist ECU
*2 Multi-media Module Receiver Assembly
*3 Accessory Meter Assembly
*4 AVC-LAN Communication Line

PROCEDURE


  1. INSPECT MULTI-MEDIA MODULE RECEIVER ASSEMBLY


    1. B00189OE61

      Remove the multi-media module receiver assembly Click here.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      7 (TX1+) - 8 (TX1-) Always 60 to 80 Ω
      45 (TX3+) - 46 (TX3-) Always 60 to 80 Ω

    NG

    REPLACE MULTI-MEDIA MODULE RECEIVER ASSEMBLY Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (AVC-LAN CIRCUIT)


    1. Disconnect the F76 multi-media module receiver assembly connector.

    2. Disconnect the F78 accessory meter assembly connector.

    3. Disconnect the F74 parking assist ECU connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      F76-45 (TX3+) - F78-7 (TX+) Always Below 1 Ω
      F76-46 (TX3-) - F78-19 (TX-) Always Below 1 Ω
      F76-7 (TX1+) - F74-11 (TX+) Always Below 1 Ω
      F76-8 (TX1-) - F74-10 (TX- ) Always Below 1 Ω
      F76-45 (TX3+) - Body ground Always 10 kΩ or higher
      F76-46 (TX3-) - Body ground Always 10 kΩ or higher
      F76-7 (TX1+) - Body ground Always 10 kΩ or higher
      F76-8 (TX1-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT MALFUNCTIONING PARTS


    1. Disconnect and reconnect each slave unit one by one until the master unit returns to normal operation.

      Tech Tips


      • Check all slave units.

      • When disconnecting a slave unit causes the master unit to return to normal operation, this indicates that the slave unit is malfunctioning. Replace the malfunctioning slave unit.

      OK
      Master unit returns to normal operation.

    OK

    REPLACE MALFUNCTIONING PARTS

    NG

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here