LIN COMMUNICATION SYSTEM Rear Heater Control Panel LIN Communication Malfunction

DESCRIPTION

The LIN communication of the components related to the rear heater occurs between the air conditioning amplifier (A/C ECU) and No. 2 air conditioning control assembly.

Tech Tips

"Rear heater control panel" refers to the rear air conditioning control panel.

WIRING DIAGRAM

A01WUOZE03

CAUTION / NOTICE / HINT

Note

When using the intelligent tester with the engine switch off to troubleshoot:

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

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - NO. 2 AIR CONDITIONING CONTROL)


    1. Disconnect the E36 amplifier connector.

    2. Disconnect the r1 or r2 air conditioning connector.

    3. Measure the resistance and voltage according to the value(s) in the tables below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      E36-20 (RLIN) - r2-16 (RLIN) Always Below 1 Ω
      E36-20 (RLIN) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      E36-20 (RLIN) - r1-10 (RLIN) Always Below 1 Ω
      E36-20 (RLIN) - Body ground Always 10 kΩ or higher
      Standard Voltage
      for LHD
      Tester Connection Condition Specified Condition
      E36-20 (RLIN) - Body ground Always Below 1 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK NO. 2 AIR CONDITIONING CONTROL ASSEMBLY (BATTERY VOLTAGE AND BODY GROUND)


    1. Disconnect the r1 or r2 air conditioning connector.

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      r2-11 (E) - Body ground Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      r1-5 (E) - Body ground Always Below 1 Ω
      Standard Voltage
      for LHD
      Tester Connection Condition Specified Condition
      r2-12 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      for RHD
      Tester Connection Condition Specified Condition
      r1-6 (IG) - Body ground Engine switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK NO. 2 AIR CONDITIONING CONTROL ASSEMBLY


    1. Temporarily replace the No. 2 air conditioning conditioning control assembly with a new or normally functioning one Click here.

    2. Check that the No. 2 air conditioning function is normal.

      OK
      No. 2 air conditioning function is normal.

    OK

    END (NO. 2 AIR CONDITIONING CONTROL ASSEMBLY IS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER Click here