Dtc B1446 Air Mix Damper Control Servo Motor Circuit (Driver Side)

Vehicle Interior. Land Cruiser. Urj200, 202 Grj200 Vdj200
Heating Air Conditioning. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (AIR MIX SERVO TARG PULSE [D])

REPLACE NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (AIR MIX DAMPER SERVO)

REPLACE AIR CONDITIONING HARNESS ASSEMBLY

DTC B1446 Air Mix Damper Control Servo Motor Circuit (Driver Side)


DESCRIPTION

The No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo) 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 air mix damper to any position. As a result, the air mix damper varies the mixture of hot air from the heater core and cold air from the evaporator so that the temperature of the air is as requested.
HINT:
Confirm that no mechanical problem is present because this trouble code may be stored when either a damper link or damper is mechanically locked.

DTC Code
DTC Detection Condition
Trouble Area
B1446
The air mix damper position does not change for 30 seconds or more when the air conditioning amplifier assembly operates the No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo).
  1. No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo)
  2. Air conditioning harness assembly
  3. Air conditioning amplifier assembly

WIRING DIAGRAM


Land Cruiser. Urj200, 202 Grj200 Vdj200.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc B1446 Air Mix Damper Control Servo Motor Circuit (Driver Side)


INSPECTION PROCEDURE

1.READ VALUE USING INTELLIGENT TESTER (AIR MIX SERVO TARG PULSE [D])

  1. Use the Data List to check if the No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo) is functioning properly (Click here).

    Air Conditioner
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    Air Mix Servo Targ Pulse (D)
    		No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo) target pulse / Min.: 0, Max.: 255
    for LHD
    1. MAX. COOL: 90 (pulse)
    2. MAX. HOT: 8 (pulse)
    for RHD
    1. MAX. COOL: 8 (pulse)
    2. MAX. HOT: 90 (pulse)
    		-
    OK:
    The display is as specified in the normal condition column.
    Result
    Result
    		Proceed to
    OK (When troubleshooting according to the DTC)
    		A
    OK (When troubleshooting according to problem symptoms table)
    		B
    NG
    		C


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

C
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Click here)
A


2.REPLACE NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY (AIR MIX DAMPER SERVO)

  1. Temporarily replace the No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo).

    1. for LHD: Click here.
    2. for RHD: Click here.
    HINT:
    Since the No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo) cannot be inspected while it is removed from the vehicle, replace the No. 1 air conditioning radiator damper servo sub-assembly (air mix damper servo) with a new or normally functioning one.

  1. Clear the DTCs (Click here).

  1. Check for DTCs (Click here).

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


B
Go to step 3
A

END (NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY [AIR MIX DAMPER SERVO] IS FAULTY)

3.REPLACE AIR CONDITIONING HARNESS ASSEMBLY

  1. Temporarily replace the air conditioning amplifier assembly with a new or normally functioning one.

    1. for LHD: Click here.
    2. for RHD: Click here.

  1. Clear the DTCs (Click here).

  1. Check for DTCs (Click here).

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


B
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Click here)
A

END (AIR CONDITIONING HARNESS ASSEMBLY IS FAULTY)