AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System with Top-mounted Air Conditioner Pressure Sensor), Diagnostic DTC:B1442

DTC Code DTC Name
B1442 Air Inlet Damper Control Servo Motor Circuit

DESCRIPTION

According to signals from the air conditioning amplifier assembly that are based on user operation or air conditioning system control, the blower motor damper servo sub-assembly (fresh/recirculation) actuates the servo motor to switch between inside and outside air intake.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B1442 Air Inlet Damper Control Servo Motor Circuit

Any of the following conditions is met:


  • No. 1 blower motor damper servo sub-assembly (fresh/recirculation) drive terminal is open circuit

  • No. 1 blower motor damper servo sub-assembly (fresh/recirculation) drive terminal is short circuit

  • No. 1 blower motor damper servo sub-assembly (fresh/recirculation)

  • Air conditioning harness assembly (heater radiator unit sub-assembly)

  • Air conditioning harness assembly (blower assembly)

  • Air conditioning amplifier assembly

Memorized

(30 seconds or more)*

DTC Detection Conditions
Vehicle Condition
Pattern 1 Pattern 2
Diagnosis Condition Ignition switch ON ○ ○
Malfunction Status No. 1 blower motor damper servo sub-assembly (fresh/recirculation) drive terminal is open circuit ○ -
No. 1 blower motor damper servo sub-assembly (fresh/recirculation) drive terminal is short circuit - ○
Detection Time 30 seconds or more 30 seconds or more
Number of Trips 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

A001VB8E01

CAUTION / NOTICE / HINT

Tech Tips

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

Click here

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (AIR INLET)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch ON.

    3. Turn the GTS on.

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

    5. 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 Inlet No. 1 blower damper servo sub-assembly (fresh/recirculation)

      Min.: 0

      Max.: 100

      Operates between

      0 to 100%

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Air Inlet
      OK
      No. 1 blower motor damper servo sub-assembly (fresh/recirculation) operates normally.
      Result
      Result Proceed to
      NG (When troubleshooting according to Problem Symptoms Table) A
      NG (When troubleshooting according to the DTC) B
      OK (When troubleshooting according to Problem Symptoms Table) C
      OK (When troubleshooting according to the DTC) D

    B

    INSPECT AIR CONDITIONING HARNESS ASSEMBLY (HEATER RADIATOR UNIT SUB-ASSEMBLY) Click here

    C

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

    D

    CHECK FOR DTC Click here

    A

  2. INSPECT NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (FRESH/RECIRCULATION) (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

  3. INSPECT AIR CONDITIONING RADIATOR ASSEMBLY (DAMPER)


    1. Remove the No. 1 blower damper servo sub-assembly (fresh/recirculation).

      Click here

    2. Operate the dampers by hand.

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

    NG

    REPLACE NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (FRESH/RECIRCULATION) Click here

    OK

  4. INSPECT AIR CONDITIONING HARNESS ASSEMBLY (HEATER RADIATOR UNIT SUB-ASSEMBLY)


    1. Remove the air conditioning harness assembly (heater radiator unit sub-assembly).

      Click here

    2. A001Y4JC03
      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)
      *b

      Front view of wire harness connector

      (to Air Conditioning Harness Assembly (blower assembly))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F7A-13 (BAI) - w-6 Always Below 1 Ω
      F7A-9 (A1AI) - w-1 Always Below 1 Ω
      F7A-3 (A2AI) - w-2 Always Below 1 Ω
      F7A-10 (B1AI) - w-3 Always Below 1 Ω
      F7A-2 (B2AI) - w-4 Always Below 1 Ω
      F7A-13 (BAI) or w-6 - Body ground Always 10 kΩ or higher
      F7A-9 (A1AI) or w-1 - Body ground Always 10 kΩ or higher
      F7A-3 (A2AI) or w-2 - Body ground Always 10 kΩ or higher
      F7A-10 (B1AI) or w-3 - Body ground Always 10 kΩ or higher
      F7A-2 (B2AI) or w-4 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY (HEATER RADIATOR UNIT SUB-ASSEMBLY Click here

    OK

  5. INSPECT AIR CONDITIONING HARNESS ASSEMBLY (BLOWER ASSEMBLY)


    1. Remove the air conditioning harness assembly (blower assembly).

      Click here

    2. A001SXSC02
      *a

      Front view of wire harness connector

      (from Air Conditioning Harness Assembly (Heater Radiator Unit Sub-assembly))
      *b

      Front view of wire harness connector

      (to No. 1 blower damper servo sub-assembly (fresh/recirculation))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      w-1 - AI-1 (A1AI) Always Below 1 Ω
      w-6 - AI-2 (BAI) Always Below 1 Ω
      w-2 - AI-3 (A2AI) Always Below 1 Ω
      w-3 - AI-4 (B1AI) Always Below 1 Ω
      w-4 - AI-6 (B2AI) Always Below 1 Ω
      w-1 or AI-1 (A1AI) - Body ground Always 10 kΩ or higher
      w-6 or AI-2 (BAI) - Body ground Always 10 kΩ or higher
      w-2 or AI-3 (A2AI) - Body ground Always 10 kΩ or higher
      w-3 or AI-4 (B1AI) - Body ground Always 10 kΩ or higher
      w-4 or AI-6 (B2AI) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY (BLOWER ASSEMBLY) Click here

    OK

  6. REPLACE NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (FRESH/RECIRCULATION)


    1. Replace the No. 1 blower damper servo sub-assembly (fresh/recirculation) with a new one or the No. 2 air conditioning radiator damper servo sub-assembly (mode switching) if it is functioning properly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  7. PERFORM ACTIVE TEST USING GTS (AIR INLET CURRENT POSITION)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch ON.

    3. Turn the GTS on.

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

    5. 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 Inlet No. 1 blower damper servo sub-assembly (fresh/recirculation)

      Min.: 0

      Max.: 100

      Operates between

      0 to 100%

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Air Inlet
      OK
      No. 1 blower motor damper servo sub-assembly (fresh/recirculation) operates normally.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 1 BLOWER DAMPER SERVO SUB-ASSEMBLY (FRESH/RECIRCULATION) Click here

    NG

  8. 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
      Result
      Result Proceed to
      DTCs are not output A
      DTCs are output B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here