AIR CONDITIONING SYSTEM, Diagnostic DTC:B1446/46

DTC Code DTC Name
B1446/46 Air Mix Damper Control Servo Motor Circuit (Driver Side)

DESCRIPTION

The No. 2 air conditioning radiator damper servo sub-assembly (driver side upper air mix) 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 air conditioning radiator damper servo sub-assembly (driver side upper air mix) to the appropriate position. As a result, the amount of air passing through the heater core after passing through the evaporator is adjusted, and the temperature of the air blowing toward the driver side is controlled.

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
B1446/46 Air Mix Damper Control Servo Motor Circuit (Driver Side) Air mix damper position sensor value does not change even if air conditioning amplifier assembly operates No. 2 air conditioning radiator damper servo sub-assembly (driver side upper air mix)
  • No. 2 air conditioning radiator damper servo sub-assembly (driver side upper air mix)

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

Memorized

(30 sec. or more)*


WIRING DIAGRAM

B004GOWE14

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.

PROCEDURE


  1. READ VALUE USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Operate the driver side temperature adjustment switch.

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

    6. Read the Data List according to the display on the GTS.


      Body Electrical > Air Conditioner > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Air Mix Servo Targ Pulse(D) No. 2 air conditioning radiator damper servo sub-assembly (driver side upper air mix) target pulse

      Min.: 128

      Max.: 383


        for LHD:

      • MAX COLD: 254 (pulse)

      • MAX HOT: 360 (pulse)


        for RHD:

      • MAX COLD: 258 (pulse)

      • MAX HOT: 152 (pulse)

      -
      Air Mix Servo Actual Pulse(D) No. 2 air conditioning radiator damper servo sub-assembly (driver side upper air mix) actual pulse

      Min.: 128

      Max.: 383


        for LHD:

      • MAX COLD: 254 (pulse)

      • MAX HOT: 360 (pulse)


        for RHD:

      • MAX COLD: 258 (pulse)

      • MAX HOT: 152 (pulse)

      -

      Body Electrical > Air Conditioner > Data List
      Tester Display
      Air Mix Servo Targ Pulse(D)
      Air Mix Servo Actual Pulse(D)
      OK
      When the driver side temperature adjustment switch is turned from MAX COLD to MAX HOT, the actual pulse changes following the target pulse.
      Result
      Result Proceed to
      Target pulse changes but actual pulse does not change A
      Target pulse and actual pulse do 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

    B
    C
    D
    A
  2. REPLACE NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (DRIVER SIDE UPPER AIR MIX)


    1. Replace the No. 2 air conditioning radiator damper servo sub-assembly (driver side upper air mix).

      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
      Result
      Result Proceed to
      DTC B1446/46 is output A
      DTC B1446/46 is not output B

    B
    A
  3. REPLACE 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
      Result
      Result Proceed to
      DTC B1446/46 is output A
      DTC B1446/46 is not output B

    A
    B
  4. RECONFIRM DTC OUTPUT


    1. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Result
      Result Proceed to
      DTC B1446/46 is output A
      DTC B1446/46 is not output B

    A
    B