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 No. 1 blower damper servo sub-assembly (air inlet 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 servo motor 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 may be stored when either a damper link or damper is mechanically locked.

DTC No. DTC Detection Condition Trouble Area
B1442/42 The air inlet servo motor position does not change when the air conditioning amplifier assembly operates the No. 1 blower damper servo sub-assembly (air inlet servo motor).

  • No. 1 blower damper servo sub-assembly (air inlet servo motor)

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

WIRING DIAGRAM

B00487UE02
*a BUS
*b No. 1 Blower Damper Servo Sub-Assembly (Air Inlet Servo Motor)
*c Air Conditioning Harness Assembly
*d Air Conditioning Amplifier Assembly

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body / Air Conditioner / Data List.

    5. According to the display on the intelligent tester, read the Data List.

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

      Air inlet servo motor target pulse /

      Min.: 0

      Max.: 255

      • Recirculation: 6 (pulse)

      • Fresh: 22 (pulse)

      		 -
      Air Inlet Damper Actual Pulse

      Air inlet servo motor actual pulse /

      Min.: 0

      Max.: 255

      		 Follows the target pulse -
      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
      NG C

    B

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

    C

    PERFORM ACTIVE TEST USING INTELLIGENT TESTER Click here

    A

  2. 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

  3. PERFORM ACTIVE TEST USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body / Air Conditioner / Active Test.

    5. According to the display on the intelligent tester, perform the Active Test.

      Air Conditioner
      Tester Display Test Part Control Range Diagnostic Note
      Air Inlet Damper Targ Pulse Air inlet damper target pulse Min.: 0, Max.: 255 Perform Active Test when value between 6 and 22 displayed
      OK
      No. 1 blower damper servo sub-assembly (air inlet servo motor) operates normally.

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

  4. REPLACE NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (AIR INLET SERVO MOTOR)


    1. Replace the No. 1 blower damper servo sub-assembly (air inlet servo motor) Click here.

      Tech Tips

      Since the No. 1 blower damper servo sub-assembly (air inlet servo motor) cannot be inspected while it is removed from the vehicle, replace the No. 1 blower damper servo sub-assembly (air inlet servo motor) with a new or normally functioning one.


    NEXT

  5. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1442/42 is not output

    OK

    END (NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (AIR INLET SERVO MOTOR) IS FAULTY)

    NG

  6. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY


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


    NEXT

  7. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1442/42 is not output

    OK

    END (AIR CONDITIONING AMPLIFIER ASSEMBLY IS FAULTY)

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here