AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System), Diagnostic DTC:B1442/42

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

DESCRIPTION

The damper servo sub-assembly 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 damper servo sub-assembly.

  • Damper servo sub-assembly

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

WIRING DIAGRAM

A01IOATE24

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 Click here

    C

    GO TO DTC B1497/97 Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

  2. READ VALUE USING INTELLIGENT TESTER


    1. Use the Data List to check if the damper servo sub-assembly is functioning properly.

      Air Conditioner
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Air Inlet Damper Targ Pulse Damper servo sub-assembly target pulse / Min.: 0, Max.: 255

      for LHD:


      • 19 (pulse): Recirculation

      • 7 (pulse): Fresh

      for RHD:


      • 7 (pulse): Recirculation

      • 25 (pulse): Fresh

      		 -
      Air Inlet Damper Actual Pulse Damper servo sub-assembly actual pulse / Min.: 0, Max.: 255

      for LHD:


      • 19 (pulse): Recirculation

      • 7 (pulse): Fresh

      for RHD:


      • 7 (pulse): Recirculation

      • 25 (pulse): Fresh

      		 -
      OK
      The display is as specified in the normal condition column.
      Result
      Result Proceed to
      OK (When troubleshooting according to the DTC) A
      OK (When troubleshooting according to Problem Symptoms Table) B
      Both target pulse and actual pulse do not display C
      Target pulse displays normally, but actual pulse does not display D

    B

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

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    D

    CHECK DAMPER SERVO SUB-ASSEMBLY Click here

    A

  3. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1442 is not output.

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  4. CHECK DAMPER SERVO SUB-ASSEMBLY


    1. Replace the damper servo sub-assembly Click here.

      Tech Tips

      Since the damper servo sub-assembly cannot be inspected while it is removed from the vehicle, replace the damper servo sub-assembly with a new or normally functioning one.

    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      OK
      DTC B1442 is not output.

    NG

    CHECK AIR CONDITIONING HARNESS ASSEMBLY Click here

    OK

    END (DAMPER SERVO SUB-ASSEMBLY IS FAULTY)

  5. CHECK AIR CONDITIONING HARNESS ASSEMBLY


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

    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      OK
      DTC B1442 is not output.

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    OK

    END (AIR CONDITIONING HARNESS ASSEMBLY IS FAULTY)