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) sends pulse signals to inform the air conditioning amplifier assembly of the damper position. The air conditioning amplifier assembly activates the motor (normal, reverse) based on the signals to move the air inlet mode selection No. 1 blower damper servo sub-assembly (air inlet) to any position, which controls the intake air settings (FRESH, FRESH/RECIRCULATION, and RECIRCULATION).

The air conditioning amplifier assembly communicates with the servo through a communication/driver IC and wiring assembly called the air conditioning harness assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory Note
B1442/42 Air Inlet Damper Control Servo Motor Circuit Air inlet damper position sensor value does not change even if air conditioning amplifier assembly operates No. 1 blower damper servo sub-assembly (air inlet)

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

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

 Memorized (30 seconds or more) -

Tech Tips

The air conditioning amplifier assembly stores the DTC of the respective malfunction if it has occurred for the period of time indicated in the brackets.

WIRING DIAGRAM

A01VAY4E02

CAUTION / NOTICE / HINT

Note

When the battery is disconnected or the air conditioning amplifier assembly is replaced, be sure to perform servo motor initialization.

Click here

Tech Tips

Confirm that no mechanical problem is present because this diagnostic code can be output when either a damper link or the damper is mechanically locked.

PROCEDURE


  1. READ VALUE USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Operate the R/F (Recirculation/Fresh) switch.

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

    6. Check the value(s) by referring to the table below.


      Body Electrical > Air Conditioner > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Air Inlet Damper Targ Pulse No. 1 blower damper servo sub-assembly (air inlet) target pulse

      Min.: 0

      Max.: 255

      for LHD:

      RECIRCULATION: 19 (pulse)

      FRESH: 7 (pulse)

      for RHD:

      RECIRCULATION: 7 (pulse)

      FRESH: 19 (pulse)

      Body Electrical > Air Conditioner > Data List
      Tester Display
      Air Inlet Damper Targ 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

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

  2. CHECK NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (AIR INLET)


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

      Click here

      Tech Tips

      Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or known good one and check that the condition returns to normal.

    2. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      OK
      DTC B1442/42 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY [AIR INLET] IS DEFECTIVE)

    NG

  3. CHECK AIR CONDITIONING HARNESS ASSEMBLY


    1. Replace the air conditioning harness assembly.

      Click here

      Tech Tips

      Since the air conditioning harness assembly cannot be inspected while it is removed from the vehicle, replace the air conditioning harness assembly with a new or known good one and check that the condition returns to normal.

    2. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      OK
      DTC B1442/42 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (AIR CONDITIONING HARNESS ASSEMBLY IS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here