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

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

DESCRIPTION

The damper servo motor (REC/FRS) 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 damper servo motor (REC/FRS) 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 output 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 motor (REC/FRS).

  • Damper servo motor (REC/FRS)

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

WIRING DIAGRAM

B001WOVE60

PROCEDURE


  1. READ VALUE USING GTS (AIR INLET DAMPER TARG PULSE, AIR INLETDAMPER ACTUAL PULSE)


    1. Use the Data List to check if the damper servo motor (REC/FRS) is functioning properly Click here.

      Air Conditioner
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Air Inlet Damper Targ Pulse Mode damper servo motor (REC/FRS) target pulse / Min.: 128, Max.: 383

        for LHD:

      • RECIRCULATION: 286 (pulse)

      • FRESH: 258 (pulse)


        for RHD:

      • RECIRCULATION: 258 (pulse)

      • FRESH: 286 (pulse)

      • Displayed between 258 and 286 pulse

      • Mode damper servo motor (REC/ FRS) system malfunction
      Air Inlet Damper Actual Pulse Mode damper servo motor (REC/FRS) target pulse / Min.: 128, Max.: 383

        for LHD:

      • RECIRCULATION: 286 (pulse)

      • FRESH: 258 (pulse)


        for RHD:

      • RECIRCULATION: 258 (pulse)

      • FRESH: 286 (pulse)

      • Displayed between 258 and 286 pulse

      • Mode damper servo motor (REC/ FRS) system malfunction
      OK
      When the mode switch is turned, the actual pulse changes following the target pulse.
      Result
      Result Proceed to
      Target pulse changes but actual pulse does not change A
      Target pulse and actual pulse do not change B
      Actual pulse changes following the target pulse (When troubleshooting according to the DTC) C
      Actual pulse changes following the target pulse (When troubleshooting according to Problem Symptoms Table) E

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    C

    CHECK FOR DTC Click here

    D

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

    A

  2. CHECK DAMPER SERVO MOTOR (REC/FRS)


    1. Replace the damper servo motor (REC/FRS).


      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

    OK

    END (DAMPER SERVO MOTOR [REC/FRS] WAS DEFECTIVE)

    B

  3. CHECK AIR CONDITIONING HARNESS ASSEMBLY


    1. Replace the air conditioning harness assembly with new or known good one.


    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      OK
      DTC B1442/42 is not output

    OK

    END (AIR CONDITIONING HARNESS ASSEMBLY WAS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  4. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1442/42 is not output

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here