LIN COMMUNICATION SYSTEM Air Conditioning Control Panel does not Operate

DESCRIPTION

The LIN communication of the components related to the air conditioning occurs between the air conditioning amplifier and air conditioning control.

WIRING DIAGRAM

A01ITX1E56

INSPECTION PROCEDURE

Note


  • When using the intelligent tester with the ignition switch off to troubleshoot:

    Connect the intelligent tester to the vehicle, and turn a courtesy light switch on and off at 1.5 second intervals until communication between the intelligent tester and vehicle begins.

  • Inspect the fuses and bulbs for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL - AIR CONDITIONING AMPLIFIER)


    1. A01IU9PE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Air Conditioning Amplifier)
      *2

      Front view of wire harness connector

      (to Air Conditioning Control)

      Disconnect the H46 amplifier connector.

    2. Disconnect the H21 control connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H21-10 (LIN1) - H46-37 (LIN1) Always Below 1 Ω
      H21-10 (LIN1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL - BATTERY AND BODY GROUND)


    1. A01IUD7E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Air Conditioning Control)

      Disconnect the H21 control connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H21-5 (GND) - Body ground Always Below 1 Ω
      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      H21-2 (IG+) - Body ground Ignition switch ON 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. REPLACE AIR CONDITIONING CONTROL ASSEMBLY


    1. Temporarily replace the air conditioning control with a new or normally functioning one Click here.

    2. Check that the air conditioning function is normal.

      OK
      Air conditioning function is normal.

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    OK

    END (REAR AIR CONDITIONING CONTROL IS DEFECTIVE)