AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System) ECO Switch Circuit

DESCRIPTION

When the ECO switch assembly (electric parking brake switch assembly) is operated, the air conditioning amplifier assembly receives a signal and enables or disables ECO mode control of the air conditioning system.

Symptom Factor
When ECO switch assembly (electric parking brake switch assembly) is operated, blower speed does not change

  • Air conditioning amplifier assembly malfunction

  • ECO switch assembly (Electric parking brake switch assembly) malfunction

  • Harness or connector

WIRING DIAGRAM

B0070AOE29

PROCEDURE


  1. READ VALUE USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Air Conditioner / Data List.

    5. Read the Data List according to the display on the GTS.


      Body Electrical > Air Conditioner > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      ECO Switch ECO switch assembly (electric parking brake switch assembly) OFF or ON

      OFF: ECO switch assembly (electric parking brake switch assembly) not pushed

      ON: ECO switch assembly (electric parking brake switch assembly) pushed and held

      		 ECO switch assembly (electric parking brake switch assembly) circuit malfunction

      Body Electrical > Air Conditioner > Data List
      Tester Display
      ECO Switch
      OK
      ECO switch assembly (electric parking brake switch assembly) condition displayed on the GTS changes with the actual switch operation.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

  2. INSPECT ECO SWITCH ASSEMBLY (ELECTRIC PARKING BRAKE SWITCH ASSEMBLY)


    1. Remove the ECO switch assembly (electric parking brake switch assembly).

      Click here

    2. Inspect the ECO switch assembly (electric parking brake switch assembly).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE ECO SWITCH ASSEMBLY (ELECTRIC PARKING BRAKE SWITCH ASSEMBLY) Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (ECO SWITCH ASSEMBLY (ELECTRIC PARKING BRAKE SWITCH ASSEMBLY) - AIR CONDITIONING AMPLIFIER ASSEMBLY AND BODY GROUND)


    1. Disconnect the K55 air conditioning amplifier assembly connector.

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

      Standard Resistance
      for LHD:
      Tester Connection Condition Specified Condition
      K37-11 (ECU) - K55-20 (ECOS) Always Below 1 Ω
      K37-16 (GND1) - Body ground Always Below 1 Ω
      K37-11 (ECU) or K55-20 (ECOS) - Other terminals and body ground Always 10 kΩ or higher
      for RHD:
      Tester Connection Condition Specified Condition
      K37-14 (ECU) - K55-20 (ECOS) Always Below 1 Ω
      K37-9 (GND1) - Body ground Always Below 1 Ω
      K37-14 (ECU) or K55-20 (ECOS) - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR