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

Lost Communication with ECM (U0100,U0142,U0155)

DESCRIPTION The air conditioning amplifier communicates with the ECM, main body ECU (multiplex network body ECU) and combination meter through the CAN communication system. DTC Code ...

Communication Malfunction (Bus Ic) (B1497)

DESCRIPTION The air conditioning harness assembly connects the No. 1 air conditioning amplifier assembly and each servo motor. The No. 1 air conditioning amplifier assembly supplies power and sen ...

Other materials about Toyota 4Runner:

Removal
REMOVAL PROCEDURE 1. REMOVE FRONT BUMPER COVER (w/o Intuitive Parking Assist System) (See Page ) 2. REMOVE FRONT BUMPER COVER (w/ Intuitive Parking Assist System) (See Page ) 3. REMOVE HIGH PITCHED HORN ASSEMBLY 4. REMOVE RADIATOR GRILLE BRACKET ...

Open in ABS Solenoid Relay Circuit (C0278,C0279)
DESCRIPTION The solenoid relay is built into the master cylinder solenoid. This relay supplies power to each solenoid. If the initial check is OK, after the ignition switch is turned to ON, the relay turns on. DTC Code DTC Detection ...