AIR CONDITIONING SYSTEM, Diagnostic DTC:B1449/49

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

DESCRIPTION

The No. 2 rear cooling unit 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 No. 2 rear cooling unit damper servo sub-assembly to the appropriate position, which controls the rear air outlet switching.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory Note
B1449/49 Rear Air Outlet Damper Control Servo Motor Circuit Rear air outlet damper position sensor value does not change even if air conditioning amplifier assembly operates No. 2 rear cooling unit damper servo sub-assembly

  • No. 2 rear cooling unit damper servo sub-assembly

  • No. 2 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 parentheses.

WIRING DIAGRAM

B006RDNE07
*a No. 2 Rear Cooling Unit Damper Servo Sub-assembly (Rear Mode)
*b No. 2 Air Conditioning Harness Assembly
*c Air Conditioning Amplifier Assembly
*d LIN Communication Line

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 DTC can be output when either a damper link or damper is mechanically locked.

PROCEDURE


  1. READ VALUE USING GTS (AIR OUTLET SERVO PULSE [R], AIR OUTLET ACTUAL PLS[R])


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Operate the mode 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 Outlet Servo Pulse (R) No. 2 rear cooling unit damper servo sub-assembly (rear mode) target pulse

      Min.: 128

      Max.: 383

      FACE: 276 (pulse)

      B/L: 228 (pulse)

      FOOT: 200 (pulse)

      • Displayed between 200 and 276 pulse

      • No. 2 rear cooling unit damper servo sub-assembly (rear mode) system malfunction
      Air Outlet Servo Actual Pls(R) No. 2 rear cooling unit damper servo sub-assembly (rear mode) actual pulse

      Min.: 128

      Max.: 383

      FACE: 276 (pulse)

      B/L: 228 (pulse)

      FOOT: 200 (pulse)

      • Displayed between 200 and 276 pulse

      • No. 2 rear cooling unit damper servo sub-assembly (rear mode) system malfunction

      Body Electrical > Air Conditioner > Data List
      Tester Display
      Air Outlet Servo Pulse (R)
      Air Outlet Servo Actual Pls(R)
      OK
      When the mode switch is operated, the actual pulse changes following the target pulse.
      Result
      Result Proceed to
      Target pulse and actual pulse do not change A
      Target pulse changes but actual pulse does not change B
      Actual pulse changes following the target pulse (When troubleshooting according to the DTC) C
      Actual pulse changes following the target pulse (When troubleshooting according to Problem Symptoms Table) D

    A

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY for LHD: Click here for RHD: Click here

    C

    CHECK FOR DTC Click here

    D

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    B

  2. CHECK NO. 2 REAR COOLING UNIT DAMPER SERVO SUB-ASSEMBLY (REAR MODE)


    1. Replace the No. 2 rear cooling unit damper servo sub-assembly (rear mode).

      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. Clear the DTC.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs

    3. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      OK
      DTC B1449/49 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (NO. 2 REAR COOLING UNIT DAMPER SERVO SUB-ASSEMBLY [REAR MODE] IS DEFECTIVE)

    NG

    CHECK HARNESS AND CONNECTOR (NO. 2 AIR CONDITIONING HARNESS ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY) Click here

  3. CHECK FOR DTC


    1. Clear the DTC.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs

    2. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      OK
      DTC B1449/49 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY for LHD: Click here for RHD: Click here

  4. CHECK HARNESS AND CONNECTOR (NO. 2 AIR CONDITIONING HARNESS ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the L18 No. 2 air conditioning harness assembly connector.

    2. Disconnect the G38 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L18-2 (RBUG) - G38-25 (RBUG) Always Below 1 Ω
      L18-3 (RBUS) - G38-1 (RBUS) Always Below 1 Ω
      L18-4 (RBBU) - G38-27 (RBBU) Always Below 1 Ω
      L18-2 (RBUG) or G38-25 (RBUG) - Body ground Always 10 kΩ or higher
      L18-3 (RBUS) or G38-1 (RBUS) - Body ground Always 10 kΩ or higher
      L18-4 (RBBU) or G38-27 (RBBU) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK NO. 2 AIR CONDITIONING HARNESS ASSEMBLY


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

      Click here

    2. Clear the DTC.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs

    3. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      OK
      DTC B1449/49 is not output.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY for LHD: Click here for RHD: Click here