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 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, reverse) based on the signals to move the No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix) to any 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 seat side is controlled.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

Note

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 air mix)

  • No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix)

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

Memorized (30 seconds or more)

-
Tip:

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

E315725E05

CAUTION / NOTICE / HINT

Note:

When the servo motor or air conditioning amplifier assembly is replaced, be sure to perform servo motor initialization.

Click here

Tip:

  • When DTC B1446/46 and DTC B1497/97 are output simultaneously, first perform troubleshooting for DTC B1497/97.

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

PROCEDURE

  1. READ VALUE USING GTS (AIR MIX SERVO TARG PULSE[D], AIR MIX SERVO ACTUAL PULSE[D])

    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. 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 Mix Servo Targ Pulse(D)

      No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix) target pulse

      Min.: 0

      Max.: 255

      • for LHD:

      • MAX. COLD: 92 (pulse)

      • MAX. HOT: 5 (pulse)

      • for RHD:

      • MAX. COLD: 6 (pulse)

      • MAX. HOT: 93 (pulse)

      • Displayed between 5 and 92 pulse (for LHD)

      • Displayed between 6 and 93 pulse (for RHD)

      • No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix) system malfunction

      Air Mix Servo Actual Pulse(D)

      No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix) actual pulse

      Min.: 0

      Max.: 255

      • for LHD:

      • MAX. COLD: 92 (pulse)

      • MAX. HOT: 5 (pulse)

      • for RHD:

      • MAX. COLD: 6 (pulse)

      • MAX. HOT: 93 (pulse)

      • Displayed between 5 and 92 pulse (for LHD)

      • Displayed between 6 and 93 pulse (for RHD)

      • No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix) system malfunction

      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 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

    Click here

    C

    CHECK FOR DTCClick here

    D

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    B

  2. CHECK NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (DRIVER SIDE AIR MIX)

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

      Click here

      Tip:

      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 DTCs.

      Click here

      Body Electrical > Air Conditioner > Clear DTCs

    3. Check for DTCs.

      Click here

      Body Electrical > Air Conditioner > Trouble Codes

      OK

      DTC B1446/46 is not output.

    Result

    Proceed to

    OK

    NG
    OK

    END (NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY WAS DEFECTIVE)

    NG

  3. CHECK AIR CONDITIONING HARNESS ASSEMBLY

    1. Replace the air conditioning harness assembly.

      Click here

      Tip:

      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. Clear the DTCs.

      Click here

      Body Electrical > Air Conditioner > Clear DTCs

    3. Check for DTCs.

      Click here

      Body Electrical > Air Conditioner > Trouble Codes

      OK

      DTC B1446/46 is not output.

    Result

    Proceed to

    OK

    NG
    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

      Body Electrical > Air Conditioner > Clear DTCs

    2. Check for DTCs.

      Click here

      Body Electrical > Air Conditioner > Trouble Codes

      OK

      DTC B1446/46 is not output.

    Result

    Proceed to

    OK

    NG
    OK

    USE SIMULATION METHOD TO CHECK

    Click hereClick hereClick here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    Click here