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

A01EU0IE01

INSPECTION PROCEDURE

Tech Tips

The navigation ECU sub-assembly is the master unit.

PROCEDURE


  1. INSPECT NAVIGATION ECU SUB-ASSEMBLY


    1. A01ETUSE04
      Text in Illustration
      *a

      Component without harness connected

      (Navigation ECU Sub-assembly)

      Disconnect the navigation ECU sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I67-7 (TX1+) - I67-8 (TX1-) Always 60 to 80 Ω

    NG

    REPLACE NAVIGATION ECU SUB-ASSEMBLY Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (NAVIGATION ECU SUB-ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY)


    1. Disconnect the navigation ECU sub-assembly connector.

    2. Disconnect the stereo component amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I69-8 (TX+) - I67-7 (TX1+) Always Below 1 Ω
      I69-7 (TX-) - I67-8 (TX1-) Always Below 1 Ω
      I69-8 (TX+) - Body ground Always 10 kΩ or higher
      I69-7 (TX-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSEMBLY - COOLER CONTROL SWITCH ASSEMBLY)


    1. Disconnect the stereo component amplifier assembly connector.

    2. Disconnect the cooler control switch assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I69-20 (TXD+) - X1-15 (TX+) Always Below 1 Ω
      I69-19 (TXD-) - X1-5 (TX-) Always Below 1 Ω
      I69-20 (TXD+) - Body ground Always 10 kΩ or higher
      I69-19 (TXD-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. 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.

    NG

    REPLACE NAVIGATION ECU SUB-ASSEMBLY Click here

    OK

    REPLACE MALFUNCTIONING PARTS