AIR CONDITIONING SYSTEM, Diagnostic DTC:B1442/42

DTC Code DTC Name
B1442/42 Air Inlet Damper Control Servo Motor Circuit

DESCRIPTION

The REC/FRS damper servo motor sends pulse signals to inform the air conditioning amplifier assembly of the damper position. The air conditioning amplifier assembly activates the motor (normal or reverse) based on the signals to move the air inlet damper to any position, which controls the intake air settings (fresh, fresh/recirculation and recirculation).

Tech Tips

Confirm that no mechanical problem is present because this trouble code can be stored when either a damper link or damper is mechanically locked.

DTC Code DTC Detection Condition Trouble Area
B1442/42 The air inlet damper position does not change even if the air conditioning amplifier assembly operates the REC/FRS damper servo motor.

  • REC/FRS damper servo motor

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

WIRING DIAGRAM

A01EQEPE28

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (REC/FRS DAMPER SERVO MOTOR)


    1. Use the Data List to check if the servo motor is functioning properly.

      Air Conditioner
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Air Inlet Damper Targ Pulse

      REC/FRS damper servo motor target pulse /

      Min.: 9, Max.: 37

      for LHD


      • Recirculation: 37 (pulse)

      • Fresh: 9 (pulse)

      for RHD


      • Recirculation: 9 (pulse)

      • Fresh: 37 (pulse)

      		 -
      OK
      The display is as specified in the normal condition.
      Result
      Result Proceed to
      OK (Checking from the DTC) A
      OK (Checking from the PROBLEM SYMPTOMS TABLE) B
      NG C

    B

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

  2. CHECK REC/FRS DAMPER SERVO MOTOR


    1. Replace the REC/FRS damper servo motor Click here.

      Tech Tips

      Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a normal one.

    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B1442/42 is not output A
      DTC B1442/42 is output B

    B

    CHECK AIR CONDITIONING HARNESS ASSEMBLY Click here

    A

    END (REC/FRS DAMPER SERVO MOTOR IS DEFECTIVE)

  3. CHECK AIR CONDITIONING HARNESS ASSEMBLY


    1. Replace the air conditioning harness assembly.


    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B1442/42 is not output A
      DTC B1442/42 is output B

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

    REPLACE END (AIR CONDITIONING HARNESS ASSEMBLY IS DEFECTIVE)