Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001H97B
Model Year Start: 2020 Model: Corolla Prod Date Range: [01/2019 - 09/2022]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): B1443; Air Outlet Damper Control Servo Motor Circuit; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]

DTC

B1443

Air Outlet Damper Control Servo Motor Circuit

DESCRIPTION

The No. 3 air conditioning radiator 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 air outlet damper to the appropriate position, which controls the air outlet switching.

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

B1443

Air Outlet Damper Control Servo Motor Circuit

Air outlet damper position sensor value does not change even if air conditioning amplifier assembly operates No. 3 air conditioning radiator damper servo sub-assembly

  • Air conditioning harness assembly
  • Air conditioning amplifier assembly
  • Air conditioning radiator assembly
  • No. 3 air conditioning radiator damper servo sub-assembly

Memorized

(30 sec. or more)*

  • *: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.

DTC Detection Condition Combination Table

 

Vehicle Condition

Pattern 1

Pattern 2

Diagnosis Condition

No. 3 air conditioning radiator damper servo sub-assembly operating

Malfunction

Air outlet damper servo operation request signals are output but the air outlet damper position sensor value does not change

-

Air outlet damper servo operation request signals are output but the air outlet damper position sensor value is abnormal

-

Detection Time

Continuously for 30 seconds or more

Continuously for 30 seconds or more

Trip Count

1 trip

1 trip

HINT:

If the conditions of either of these patterns are detected, a DTC will be stored

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • This DTC is also output for the damper link, damper lock, etc. Before performing inspection, perform servomotor initialization and check that there are no mechanical malfunctions.

    Click here 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): INITIALIZATION

  • This DTC is also output when servomotor initialization has failed. When servomotor initialization has failed, repair any malfunctions and perform servomotor initialization again.

    Click here 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): INITIALIZATION

PROCEDURE

1.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Trouble Codes.

(e) Check for DTCs.

Body Electrical > Air Conditioner > Trouble Codes

Result

Proceed to

B1497 is not output

A

B1497 is output

B

B

GO TO DTC B1497

A

2.

INSPECT NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (INSTALLATION CONDITION)

(a) Check that the No. 3 air conditioning radiator damper servo sub-assembly is installed correctly.

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OK:

The No. 3 air conditioning radiator damper servo sub-assembly is installed correctly.

NG

INSTALL NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY CORRECTLY

OK

3.

INSPECT NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (MOTOR, LINK, DAMPER)

(a) 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.

NG

REMOVE PINCHED WIRE HARNESS

OK

4.

INSPECT AIR CONDITIONING RADIATOR ASSEMBLY (DAMPER)

(a) Remove the No. 3 air conditioning radiator damper servo sub-assembly.

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(b) Operate the dampers by hand.

OK:

The dampers are easily operated by hand.

NG

REPLACE AIR CONDITIONING RADIATOR ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: REMOVAL 2020 - 2021 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 06/2021]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: REMOVAL 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2021 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: REMOVAL

OK

5.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Remove the No. 2 air conditioning radiator damper servo sub-assembly.

Click here 2020 - 2021 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 06/2020]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2020 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY

(b) Connect the No. 2 air conditioning radiator damper servo sub-assembly connector to the No. 3 air conditioning radiator damper servo sub-assembly.

(c) Connect the Techstream to the DLC3.

(d) Turn the power switch on (IG).

(e) Turn the Techstream on.

(f) Enter the following menus: Body Electrical / Air Conditioner / Active Test.

(g) Perform the Active Test according to the display on the Techstream.

Body Electrical > Air Conditioner > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

A/O Servo Pulse(Rr D)

No. 2 air conditioning radiator damper servo sub-assembly pulse*

Min.: 128

Max.: 383

Operates between 250 and 297 pulses

  • *: Thus this Active Test is for the No. 2 air conditioning radiator damper servo sub-assembly, in this case it is used to check the operation of the No. 3 air conditioning radiator damper servo sub-assembly.

Body Electrical > Air Conditioner > Active Test

Tester Display

A/O Servo Pulse(Rr D)

OK:

The No. 3 air conditioning radiator damper servo sub-assembly operates.

OK

REPLACE AIR CONDITIONING HARNESS ASSEMBLY 2020 - 2021 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 06/2020]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2020 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY

NG

REPLACE NO. 3 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY 2020 - 2021 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 06/2020]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2020 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY