AIR CONDITIONING SYSTEM, Diagnostic DTC:B1449/49

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

DESCRIPTION

The No. 3 air conditioning radiator 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 these signals to move the air mix damper to the appropriate position, which controls the rear air outlet switching. 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
B1449/49 Rear Air Outlet Damper Control Servo Motor Circuit Air mix damper position sensor value does not change even if air conditioning amplifier assembly operates No. 3 air conditioning radiator damper servo sub-assembly

  • No. 3 air conditioning radiator damper servo sub-assembly

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

  • Air conditioning radiator assembly

Memorized

(30 sec. or more)*

WIRING DIAGRAM

A003OBFE09

CAUTION / NOTICE / HINT

Tech Tips


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

  • When installing the damper servo motor, make sure to install it correctly.

    Click here

PROCEDURE


  1. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Result
      Result Proceed to
      DTC B1497/97 is not output A
      DTC B1497/97 is output B

    B

    GO TO DTC B1497/97 Click here

    A

  2. INSTALL NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY CORRECTLY


    1. Check that the No. 3 air conditioning radiator damper servo sub-assembly is installed correctly.

      Click here

      OK
      The No. 3 air conditioning radiator damper servo sub-assembly is installed correctly.
      Result
      Proceed to
      OK
      NG

    NG

    INSTALL NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY CORRECTLY

    OK

  3. INSPECT NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (MOTOR, LINK, DAMPER)


    1. Check for a wire harness caught between the links of the motors and dampers.

      OK
      No wire harnesses are caught between the links of the motors and dampers.
      Result
      Proceed to
      OK
      NG

    NG

    REMOVE PINCHED WIRE HARNESS

    OK

  4. INSPECT AIR CONDITIONING RADIATOR ASSEMBLY (DAMPER)


    1. Remove the No. 3 air conditioning radiator damper servo sub-assembly.

      Click here

    2. Operate the dampers by hand.

      OK
      The dampers are easily operated by hand.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE AIR CONDITIONING RADIATOR ASSEMBLY Click here

    OK

  5. PERFORM ACTIVE TEST USING GTS


    1. Remove the No. 1 air conditioning radiator damper servo sub-assembly.

      Click here

    2. Connect the No. 1 air conditioning radiator damper servo sub-assembly connector to the No. 3 air conditioning radiator damper servo sub-assembly.

    3. Connect the GTS to the DLC3.

    4. Turn the power switch on (IG).

    5. Turn the GTS on.

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

    7. Perform the Active Test according to the display on the GTS.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Air Outlet Servo Pulse (P) No. 1 air conditioning radiator damper servo sub-assembly pulse*

      Min.: 128

      Max.: 383

      		 Operates between 164 to 256 pulses

      • *: Thus this Active Test is for the No. 1 air conditioning radiator damper servo sub-assembly, in this case it is used to check the operation of the No. 3 air conditioning radiator damper servo sub-assembly.


      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Air Outlet Servo Pulse (P)
      OK
      The No. 3 air conditioning radiator damper servo sub-assembly operates.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here

    NG

    REPLACE NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY Click here