AIR CONDITIONING SYSTEM, Diagnostic DTC:B1442/42

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

DESCRIPTION

The recirculation 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).

Tip:

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.

Detection Item

DTC Detection Condition

Trouble Area

Memory

Note

B1442/42

Air Inlet Damper Control Servo Motor Circuit

The air inlet damper position does not change when the air conditioning amplifier assembly operates the recirculation damper servo sub-assembly.

  • Recirculation damper servo sub-assembly

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

Stored

(30 seconds or more)

-

WIRING DIAGRAM

E180810E82

PROCEDURE

  1. CHECK FOR DTC

    1. Clear the DTCs

      Click here

      Body Electrical > Air Conditioner > Clear DTCs

    2. Check for DTCs

      Click here

      Body Electrical > Air Conditioner > Trouble Codes

    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
    A

    USE SIMULATION METHOD TO CHECK

    Click hereClick here

    C

    GO TO DTC B1497/97

    Click here

    B

  2. READ VALUE USING INTELLIGENT TESTER (RECIRCULATION DAMPER SERVO)

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

      Click here

      Body Electrical > Air Conditioner > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      Air Inlet Damper Targ Pulse

      Recirculation damper servo sub-assembly target pulse

      Min.: 0, Max.: 255

      7 (pulse): Recirculation

      28 (pulse): Fresh

      -

      Air Inlet Damper Actual Pulse

      Recirculation damper servo sub-assembly actual pulse

      Min.: 0, Max.: 255

      7 (pulse): Recirculation

      28 (pulse): Fresh

      -

      OK

      The display is as specified in the normal condition column.

    Result

    Result

    Proceed to

    OK (When troubleshooting according to problem symptoms table)

    A

    OK (When troubleshooting according to the DTC)

    B

    NG

    C
    A

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    Click here

    C

  3. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (RECIRCULATION DAMPER SERVO)

    1. Select the Active Test, use the intelligent tester to generate a control command, and then check that the recirculation damper servo sub-assembly operates

      Click here

      Body Electrical > Air Conditioner > Active Test

      Tester Display

      Measurement Item

      Control Range

      Diagnostic Note

      Air Inlet Damper Targ Pulse

      Recirculation damper servo sub-assembly target pulse

      Min.: 0, Max.: 255

      -

      OK

      Recirculation damper servo sub-assembly operates normally.

    Result

    Result

    OK

    NG
    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    Click here

    NG

  4. REPLACE RECIRCULATION DAMPER SERVO SUB-ASSEMBLY

    1. Replace the recirculation damper servo sub-assembly

      Click here

      Tip:

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

    Result

    Result

    NEXT
    NEXT

  5. CHECK FOR DTC

    1. Clear the DTCs

      Click here

      Body Electrical > Air Conditioner > Clear DTCs

    2. Check for DTCs

      Click here

      Body Electrical > Air Conditioner > Trouble Codes

      OK

      DTC B1442 is not output.

    Result

    Result

    OK

    NG
    OK

    END (RECIRCULATION DAMPER SERVO SUB-ASSEMBLY IS FAULTY)

    NG

  6. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    1. Replace the air conditioning amplifier assembly with a new or normally functioning one

      Click here

    Result

    Result

    NEXT
    NEXT

  7. CHECK FOR DTC

    1. Clear the DTCs

      Click here

      Body Electrical > Air Conditioner > Clear DTCs

    2. Check for DTCs

      Click here

      Body Electrical > Air Conditioner > Trouble Codes

      OK

      DTC B1442 is not output.

    Result

    Result

    OK

    NG
    OK

    END (AIR CONDITIONING AMPLIFIER ASSEMBLY IS FAULTY)

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY

    Click here