AUDIO AND VISUAL SYSTEM(for 8 Speakers) AVC-LAN Circuit

DESCRIPTION

Each unit of the audio and visual system connected to the AVC-LAN (communication bus) transmits switch signals via the AVC-LAN communication.

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

WIRING DIAGRAM

A0004X9E05

CAUTION / NOTICE / HINT

Tech Tips

The radio receiver assembly is the master unit.

PROCEDURE


  1. INSPECT RADIO RECEIVER ASSEMBLY


    1. Remove the radio receiver assembly Click here.

    2. A0005HPE02
      Text in Illustration
      *a

      Component without harness connected

      (Radio Receiver Assembly)
      A000887E02
      Text in Illustration
      *a

      Component without harness connected

      (Radio Receiver Assembly)
      A0004IRE02
      Text in Illustration
      *a

      Component without harness connected

      (Radio Receiver Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H177-18 (TX2+) - H177-19 (TX2-) Always 60 to 80 Ω
      H176-7 (TX1+) - H176-8 (TX1-) Always 60 to 80 Ω
      H178-11 (TX4+) - H178-12 (TX4-) Always 60 to 80 Ω

    NG

    REPLACE RADIO RECEIVER ASSEMBLY Click here

    OK

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


    1. Disconnect the H176, H177 and H178 radio receiver assembly connectors.

    2. Disconnect the H87 stereo component amplifier assembly connector.

    3. Disconnect the H93 multi-display assembly connector.

    4. Disconnect the H181 remote operation board connector.

    5. Disconnect the j2 rear control switch connector (w/ Rear Control Switch).

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H176-7 (TX1+) - H87-8 (TX+) Always Below 1 Ω
      H176-8 (TX1-) - H87-7 (TX-) Always Below 1 Ω
      H178-11 (TX4+) - H93-7 (TX+) Always Below 1 Ω
      H178-12 (TX4-) - H93-19 (TX-) Always Below 1 Ω
      H177-18 (TX2+) - H181-10 (TX+) Always Below 1 Ω
      H177-19 (TX2-) - H181-11 (TX-) Always Below 1 Ω
      H93-6 (TX1+) - j2-15 (TX+)* Always Below 1 Ω
      H93-18 (TX1-) - j2-5 (TX-)* Always Below 1 Ω
      H176-7 (TX1+) - Body ground Always 10 kΩ or higher
      H176-8 (TX1-) - Body ground Always 10 kΩ or higher
      H178-11 (TX4+) - Body ground Always 10 kΩ or higher
      H178-12 (TX4-) - Body ground Always 10 kΩ or higher
      H177-18 (TX2+) - Body ground Always 10 kΩ or higher
      H177-19 (TX2-) - Body ground Always 10 kΩ or higher
      H93-6 (TX1+) - Body ground* Always 10 kΩ or higher
      H93-18 (TX1-) - Body ground* Always 10 kΩ or higher

      • *: w/ Rear Control Switch


    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.

      Tech Tips


      • Check all slave units.

      • If disconnecting a slave unit causes the master unit to return to normal, the slave unit is defective and should be replaced.

      OK
      Master unit returns to normal.

    OK

    REPLACE MALFUNCTIONING PARTS

    NG

    REPLACE RADIO RECEIVER ASSEMBLY Click here