AIR CONDITIONING SYSTEM, Diagnostic DTC:B1448/48

DTC Code DTC Name
B1448/48 Passenger Side FACE Servo Motor Circuit

DESCRIPTION


The mode damper servo motor RH*1 or LH*2 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 mode damper servo motor RH*1 or LH*2 to any position, which controls the air outlet changes.

Tech Tips

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

DTC Code DTC Detection Condition Trouble Area
B1448/48 The air outlet damper position does not change even if the air conditioning amplifier assembly operates the air outlet damper servo motor.

  • Mode damper servo motor RH*1

  • Mode damper servo motor LH*2

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

WIRING DIAGRAM

B00190HE78

PROCEDURE


  1. READ VALUE USING GTS (AIR OUTLET SERVO TARG[P], AIR OUTLET SERVO ACTU[P])


    • *1: for LHD

    • *2: for RHD


    1. Use the Data List to check if the mode damper servo motor RH*1 or LH*2 is functioning properly Click here.

      Air Conditioner
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Air Outlet Servo Targ Pulse(P) Mode pamper servo motor RH*1 or LH*2 target pulse / Min.: 128, Max.: 383

        for LHD:

      • FACE: 254 (pulse)

      • FACE1: 246 (pulse)

      • FACE2: 254 (pulse)

      • B/L1: 230 (pulse)

      • B/L2: 218 (pulse)

      • FOOT-O: 208 (pulse)

      • FOOT-D: 189 (pulse)

      • FOOT-R: 178 (pulse)

      • FOOT-F: 178 (pulse)

      • FOOT 178 (pulse)

      • F/D: 155 (pulse)

      • DEF: 143 (pulse)


        for RHD:

      • FACE: 258 (pulse)

      • FACE1: 266 (pulse)

      • FACE2: 258 (pulse)

      • B/L1: 282 (pulse)

      • B/L2: 294 (pulse)

      • FOOT-O: 304 (pulse)

      • FOOT-D: 323 (pulse)

      • FOOT-R: 334 (pulse)

      • FOOT-F: 334 (pulse)

      • FOOT 334 (pulse)

      • F/D: 357 (pulse)

      • DEF: 369 (pulse)

      • Displayed between 143 and 254 pulse (for LHD)

      • Displayed between 258 and 369 pulse (for RHD)

      • Mode damper servo motor RH*1 or LH*2 system malfunction
      Air Outlet Servo Actu Pulse(P) Mode pamper servo motor RH*1 or LH*2 actual pulse / Min.: 128, Max.: 383

        for LHD:

      • FACE: 254 (pulse)

      • FACE1: 246 (pulse)

      • FACE2: 254 (pulse)

      • B/L1: 230 (pulse)

      • B/L2: 218 (pulse)

      • FOOT-O: 208 (pulse)

      • FOOT-D: 189 (pulse)

      • FOOT-R: 178 (pulse)

      • FOOT-F: 178 (pulse)

      • FOOT 178 (pulse)

      • F/D: 155 (pulse)

      • DEF: 143 (pulse)


        for RHD:

      • FACE: 258 (pulse)

      • FACE1: 266 (pulse)

      • FACE2: 258 (pulse)

      • B/L1: 282 (pulse)

      • B/L2: 294 (pulse)

      • FOOT-O: 304 (pulse)

      • FOOT-D: 323 (pulse)

      • FOOT-R: 334 (pulse)

      • FOOT-F: 334 (pulse)

      • FOOT 334 (pulse)

      • F/D: 357 (pulse)

      • DEF: 369 (pulse)

      • Displayed between 143 and 254 pulse (for LHD)

      • Displayed between 258 and 369 pulse (for RHD)

      • Mode damper servo motor RH*1 or LH*2 system malfunction
      OK
      When the front passenger side mode switch is turned, 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

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    C

    CHECK FOR DTC Click here

    D

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

    A

  2. CHECK MODE DAMPER SERVO MOTOR (for Front Passenger Side)


    1. for LHD:


      1. Replace the mode damper servo motor RH Click here.

    2. for RHD:


      1. Replace the mode damper servo motor LH 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.

    3. Clear the DTCs Click here.

    4. Check for DTCs Click here.

      OK
      DTC B1448/482 is not output.

    OK

    END (AIR MODE DAMPER SERVO MOTOR [for Front Passenger Side] WAS DEFECTIVE)

    NG

  3. CHECK AIR CONDITIONING HARNESS ASSEMBLY


    1. Replace the air conditioning harness assembly with a new or known one Click here.

    2. Clear the DTCs Click here.

    3. Check for DTCs Click here.

      OK
      DTC B1448/482 is not output.

    OK

    END (AIR CONDITIONING HARNESS ASSEMBLY WAS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  4. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1448/482 is not output.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here