AIR CONDITIONING SYSTEM, Diagnostic DTC:B1442/42

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

DESCRIPTION

The air inlet damper servo sends pulse signals to inform the air conditioning amplifier of the damper position. The air conditioning amplifier activates the motor (normal, 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 diagnostic code can be output when either a damper link or damper is mechanically locked.

DTC Code DTC Detection Condition Trouble Area
B1442/42 Air inlet damper position sensor value does not change even if air conditioning amplifier operates air inlet damper servo motor

  • Air inlet servo motor

  • Air conditioning harness

  • Air conditioning amplifier

WIRING DIAGRAM

A01H0AAE41

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B1442/42 is not output A
      DTC B1442/42 is output B
      DTC B1442/42 and B1497/97 are output C

    B

    READ VALUE USING INTELLIGENT TESTER (AIR INLET DAMPER TARGET PULSE) Click here

    C

    GO TO DTC B1497/97 Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

  2. READ VALUE USING INTELLIGENT TESTER (AIR INLET DAMPER TARGET PULSE)


    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 Target Pulse

      Air inlet damper target pulse /

      for LHD Min.: 8, Max.: 31

      for RHD Min.: 7, Max.: 30

      for LHD:


      • RECIRCULATION: 8 (pulse)

      • FRESH: 31 (pulse)

      for RHD:


      • RECIRCULATION: 30 (pulse)

      • FRESH: 7(pulse)

      		 -
      OK
      The display is as specified in the normal condition.

    2. Visually inspect the air inlet servo motor.


      1. Visually inspect whether the air inlet servo motor operates.

        OK
        The air inlet servo motor operates.
        Result
        Result Proceed to
        The Data List value changes and the air inlet servo motor operates (When troubleshooting according to the DTC output) A
        The Data List value changes and the air inlet servo motor operates (When troubleshooting according to Problem Symptoms Table) B
        The Data List value does not change and the air inlet servo motor does not operate C
        The Data List value changes, but the air inlet servo motor does not operate D

    B

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    C

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    D

    CHECK AIR INLET SERVO MOTOR Click here

    A

  3. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1442/42 is not output.

    NG

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  4. CHECK AIR INLET SERVO MOTOR


    1. Replace the air inlet 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.

      OK
      DTC B1442/42 is not output.

    NG

    CHECK AIR CONDITIONING HARNESS Click here

    OK

    END (AIR INLET SERVO MOTOR IS FAULTY)

  5. CHECK AIR CONDITIONING HARNESS


    1. Replace the air conditioning harness Click here.

    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      OK
      DTC B1442/42 is not output.

    NG

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    OK

    END (AIR CONDITIONING HARNESS IS FAULTY)