Toyota 4Runner: Air Outlet Damper Control Servo Motor Circuit (B1443)

Toyota 4Runner Service Manual / Vehicle Interior / Heating / Air Conditioning / Air Conditioning System(for Manual Air Conditioning System) / Air Outlet Damper Control Servo Motor Circuit (B1443)

DESCRIPTION

The damper servo sub-assembly (mode damper servo) sends pulse signals to inform the No. 1 air conditioning amplifier assembly of the damper position. The No. 1 air conditioning amplifier assembly activates the motor (normal or reverse) based on the signals to move the air outlet damper to any position, which controls the air outlet changes.

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
B1443	The air outlet damper position does not change when the No. 1 air conditioning amplifier assembly operates the damper servo sub-assembly (mode damper servo).	Damper servo sub-assembly (mode damper servo) Air conditioning harness assembly No. 1 air conditioning amplifier assembly

WIRING DIAGRAM

PROCEDURE

1.	READ VALUE USING TECHSTREAM (MODE DAMPER SERVO)

(a) Use the Data List to check if the damper servo sub-assembly (mode damper servo) is functioning properly (See page ).

Air Conditioner

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Air Outlet Servo Pulse (D)	Damper servo sub-assembly (mode damper servo) actual pulse / Min.: 0, Max.: 255	15 (pulse): FACE 41 (pulse): B/L 65 or 73 (pulse): FOOT 83 or 95 (pulse): F/D 113 (pulse): DEF	-
Air Outlet Servo Actu Pulse (D)	Damper servo sub-assembly (mode damper servo) actual pulse / Min.: 0, Max.: 255	15 (pulse): FACE 41 (pulse): B/L 65 or 73 (pulse): FOOT 83 or 95 (pulse): F/D 113 (pulse): DEF	-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Air Outlet Servo Pulse (D)

Damper servo sub-assembly (mode damper servo) actual pulse / Min.: 0, Max.: 255

15 (pulse): FACE

41 (pulse): B/L

65 or 73 (pulse): FOOT

83 or 95 (pulse): F/D

113 (pulse): DEF

Air Outlet Servo Actu Pulse (D)

Damper servo sub-assembly (mode damper servo) actual pulse / Min.: 0, Max.: 255

15 (pulse): FACE

41 (pulse): B/L

65 or 73 (pulse): FOOT

83 or 95 (pulse): F/D

113 (pulse): DEF

OK:

The display is as specified in the normal condition column.

Result

Result	Proceed to
OK (When troubleshooting according to problem symptoms table)	A
OK (When troubleshooting according to the DTC)	B
NG	C

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE NO. 1 AIR CONDITIONING AMPLIFIER ASSEMBLY

2.	PERFORM ACTIVE TEST USING TECHSTREAM (MODE DAMPER SERVO)

(a) Select the Active Test, use the Techstream to generate a control command, and then check that the damper servo sub-assembly (mode damper servo) operates (See page ).

Air Conditioner

Tester Display	Test Part	Control Range	Diagnostic Note
Air Outlet Servo Pulse (D)	Damper servo sub-assembly (mode damper servo) pulse	Min.: 0, Max.: 255	-

OK:

Damper servo sub-assembly (mode damper servo) operates normally.

REPLACE NO. 1 AIR CONDITIONING AMPLIFIER ASSEMBLY

3.	REPLACE DAMPER SERVO SUB-ASSEMBLY (MODE DAMPER SERVO)

(a) Replace the damper servo sub-assembly (mode damper servo) (See page ).

HINT:

Since the damper servo sub-assembly (mode damper servo) cannot be inspected while it is removed from the vehicle, replace the damper servo sub-assembly (mode damper servo) with a new or normally functioning one.

4.	CHECK FOR DTC

(a) Clear the DTCs (See page ).

(b) Check for DTCs (See page ).

OK:

DTC B1443 is not output.

END (DAMPER SERVO SUB-ASSEMBLY [MODE DAMPER SERVO] IS FAULTY)

5.	REPLACE NO. 1 AIR CONDITIONING AMPLIFIER ASSEMBLY

(a) Temporarily replace the No. 1 air conditioning amplifier assembly with a new or normally functioning one (See page ).

6.	CHECK FOR DTC

(a) Clear the DTCs (See page ).

(b) Check for DTCs (See page ).

OK:

DTC B1443 is not output.

END (NO. 1 AIR CONDITIONING AMPLIFIER ASSEMBLY IS FAULTY)

REPLACE AIR CONDITIONING HARNESS ASSEMBLY

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