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 (air inlet control) sends pulse signals to indicate the damper position to the air conditioning amplifier. The air conditioning amplifier activates the motor (normal or reverse) based on these signals to move the air inlet control damper to the appropriate position, which controls the intake air settings (FRESH, FRESH / RECIRCULATION and RECIRCULATION).

Tech Tips

Confirm that there are no mechanical problems because this DTC can be set ifeither a damper link or damper is mechanically locked.

DTC No. DTC Detection Condition Trouble Area
B1442/42 Air inlet damper position does not change even if air conditioning amplifier operates air inlet damper control servo motor

  • Air inlet control servo motor

  • Air conditioning harness

  • Air conditioning amplifier

WIRING DIAGRAM

A017DCOE10

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (A/I DAMP TARG PLS)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch on (IG) and turn the intelligent tester main switch on.

    3. Select the item below in the Data List, and read the value displayed on the intelligent tester.

      Data List / Air Conditioner:
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      A/I Damp Targ Pls

      Air inlet damper target pulse /

      Min.: 0, Max.: 255

      RECIRCULATION: 7 (pulse)

      FRESH: 28 (pulse)

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

    B

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

    C

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    A

  2. REPLACE AIR INLET CONTROL SERVO MOTOR

    Tech Tips

    Since the servo motor cannot be tested when it is removed from the vehicle, replace the servo motor with a normal one and check that the condition returns to normal.

    OK
    Same problem does not occur.

    NEXT

  3. CHECK DTC OUTPUT


    1. Check for DTC.

      OK
      DTC B1442/42 is not output.

    NG

    REPAIR OR REPLACE AIR CONDITIONING HARNESS

    OK

    END