NAVIGATION SYSTEM AVC-LAN Circuit

DESCRIPTION

Each unit of the navigation system connected to the AVC-LAN (communication bus) transfers the switch signals using the AVC-LAN.

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

WIRING DIAGRAM

A005DXEE25

CAUTION / NOTICE / HINT

Tech Tips

The navigation ECU sub-assembly is the master unit.

PROCEDURE


  1. INSPECT NAVIGATION ECU SUB-ASSEMBLY


    1. A0059S4E01
      Text in Illustration
      *a

      Component without harness connected

      (Navigation ECU Sub-assembly)

      Disconnect the L38 and L37 navigation ECU sub-assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L38-7 (TX1+) - L38-8 (TX1-) Always 60 to 80 Ω
      L37-3 (TX3+) - L37-4 (TX3-) Always 60 to 80 Ω

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


    1. Disconnect the L38 and L37 navigation ECU sub-assembly connectors.

    2. Disconnect the L31 stereo component amplifier assembly connector.

    3. Disconnect the L64 parking assist ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L31-8 (ATX+) - L38-7 (TX1+) Always Below 1 Ω
      L31-7 (ATX-) - L38-8 (TX1-) Always Below 1 Ω
      L64-11 (TX+) - L37-3 (TX3+) Always Below 1 Ω
      L64-10 (TX-) - L37-4 (TX3-) Always Below 1 Ω
      L31-8 (ATX+) - Body ground Always 10 kΩ or higher
      L31-7 (ATX-) - Body ground Always 10 kΩ or higher
      L64-11 (TX+) - Body ground Always 10 kΩ or higher
      L64-10 (TX-) - Body ground Always 10 kΩ or higher

    NG
    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.

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

      OK
      Master unit returns to normal operation.

    OK
    NG