AIR CONDITIONING SYSTEM, Diagnostic DTC:B1449/49

DTC Code DTC Name
B1449/49 Rear Air Outlet Damper Control Servo Motor Circuit

DESCRIPTION

The rear air outlet damper 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 rear air outlet damper to the appropriate position, which controls the air outlet modes.

Tech Tips

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

DTC Code DTC Detection Condition Trouble Area
B1449/49 The rear air outlet damper position does not change even if the air conditioning amplifier assembly operates the rear air outlet damper servo motor.

  • Rear air outlet damper servo motor

  • No. 2 air conditioning harness assembly

  • Harness or connector between No. 2 air conditioning harness assembly and air conditioning amplifier assembly

  • Air conditioning amplifier assembly

WIRING DIAGRAM

A01EQTVE03

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (REAR AIR OUTLET DAMPER SERVO MOTOR)


    1. Use the Data List to check if the servo motor is functioning properly.

      Air Conditioner
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Air Outlet Servo Pulse (R)

      Rear air outlet damper servo motor target pulse /

      Min.: 7, Max.: 83

      FOOT: 7 (pulse)

      B/L: 42 (pulse)

      FACE: 83 (pulse)

      		 -
      OK
      The display is as specified in the normal condition.
      Result
      Result Proceed to
      OK (Checking from the DTC) A
      OK (Checking from the 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 HARNESS AND CONNECTOR (NO. 2 AIR CONDITIONING HARNESS - AIR CONDITIONING AMPLIFIER)

    A01EOI2E02

    1. Disconnect the K19 No. 2 air conditioning harness assembly connector.

    2. Disconnect the E36 amplifier connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      K19-2 (RBUG) - E36-12 (RBUG) Always Below 1 Ω
      K19-3 (RBUS) - E36-13 (RBUS)
      K19-4 (RBBU) - E36-14 (RBBU)
      E36-12 (RBUG) - Body ground Always 10 kΩ or higher
      E36-13 (RBUS) - Body ground
      E36-14 (RBBU) - Body ground

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK REAR AIR OUTLET DAMPER SERVO MOTOR


    1. Replace the rear air outlet damper servo motor Click here.

      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.

      Result
      Result Proceed to
      DTC B1449/49 is not output A
      DTC B1449/49 is output B

    B

    CHECK NO. 2 AIR CONDITIONING HARNESS ASSEMBLY Click here

    A

    END (REAR AIR OUTLET DAMPER SERVO MOTOR IS DEFECTIVE)

  4. CHECK NO. 2 AIR CONDITIONING HARNESS ASSEMBLY


    1. Replace the No. 2 air conditioning harness assembly Click here.

    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B1449/49 is not output A
      DTC B1449/49 is output B

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

    END (NO. 2 AIR CONDITIONING HARNESS ASSEMBLY IS DEFECTIVE) Click here