AIR CONDITIONING SYSTEM, Diagnostic DTC:B1456/56

DTC Code DTC Name
B1456/56 Passenger Side Air Outlet Damper FOOT/DEF Control Servo Motor Circuit

DESCRIPTION

The mode damper servo (for passenger side FOOT/DEF) sends pulse signals to inform the air conditioning amplifier of the damper position. The air conditioning amplifier activates the motor (normal, reverse) based on the signals to move the mode damper servo (for passenger side FOOT/DEF) to any position, which controls the air outlet changes.

Tech Tips

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

DTC Code DTC Detection Condition Trouble Area
B1456/56 Air outlet damper position sensor value does not change even if air conditioning amplifier operates air outlet servo motor

  • Air outlet servo motor (for passenger side FOOT/DEF)

  • Air conditioning harness

  • Air conditioning amplifier

WIRING DIAGRAM

A01H0AAE50

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B1456/56 is not output A
      DTC B1456/56 is output B
      DTC B1456/56 and B1497/97 are output C

    B

    READ VALUE USING INTELLIGENT TESTER (AIR OUTLET SERVO MOTOR TARGET PULSE (for Passenger Side FOOT/DEF)) Click here

    C

    GO TO DTC B1497/97 Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

  2. READ VALUE USING INTELLIGENT TESTER (AIR OUTLET SERVO MOTOR TARGET PULSE (for Passenger Side FOOT/DEF))


    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
      A/O Damper FOOT/DEF Pos(P)

      Passenger side FOOT/DEF air outlet servo motor target pulse /

      for LHD Min.: 26, Max.: 96

      for RHD Min.: 86, Max.: 156

      for LHD:


      • FACE: 26 to 36 (pulse)

      • B/L 1&2: 44 (pulse)

      • FOOT: 44to 69 (pulse)

      • FOOT/DEF: 86 (pulse)

      • DEF: 96 (pulse)

      for RHD:


      • FACE: 146 to 156 (pulse)

      • B/L 1&2: 138 (pulse)

      • FOOT: 113 to 138 (pulse)

      • FOOT/DEF: 96 (pulse)

      • DEF: 86 (pulse)

      		 -
      OK
      The display is as specified in the normal condition.

    2. Visually inspect the air outlet servo motor (for passenger side FOOT/DEF).


      1. Visually inspect whether the air outlet servo motor (for passenger side FOOT/DEF) operates.

        OK
        The air outlet servo motor (for passenger side FOOT/DEF) operates.
        Result
        Result Proceed to
        The Data List value changes and the air outlet servo motor (for passenger side FOOT/DEF) operates (When troubleshooting according to the DTC output) A
        The Data List value changes and the air outlet servo motor (for passenger side FOOT/DEF) operates (When troubleshooting according to Problem Symptoms Table) B
        The Data List value does not change and the air outlet servo motor (for passenger side FOOT/DEF) does not operate C
        The Data List value changes, but the air outlet servo motor (for passenger side FOOT/DEF) does not operate D

    B

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

    C

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    D

    CHECK AIR OUTLET SERVO MOTOR (for Passenger Side FOOT/DEF) Click here

    A

  3. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1456/56 is not output.

    NG

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  4. CHECK AIR OUTLET SERVO MOTOR (for Passenger Side FOOT/DEF)


    1. Replace the air outlet 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.

      OK
      DTC B1456/56 is not output.

    NG

    CHECK AIR CONDITIONING HARNESS Click here

    OK

    END (AIR OUTLET SERVO MOTOR (for Passenger Side FOOT/DEF) IS FAULTY)

  5. CHECK AIR CONDITIONING HARNESS


    1. Replace the air conditioning harness Click here.

    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      OK
      DTC B1456/56 is not output.

    NG

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    OK

    END (AIR CONDITIONING HARNESS IS FAULTY)