Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VK12
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 - 08/2016]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1441/41; Air Mix Damper Control Servo Motor Circuit (Passenger Side); 2016 MY Sienna [12/2015 - 08/2016]

DTC

B1441/41

Air Mix Damper Control Servo Motor Circuit (Passenger Side)

DESCRIPTION

The air mix control servo motor sends pulse signals to indicate the damper position to the air conditioning amplifier. The air conditioning amplifier activates the motor (normal or reverse) based on these signals to move the air mix damper (front passenger side) to any position. As a result, the amount of air passing through the heater core after passing through the evaporator is adjusted, and the temperature of the air blowing toward the passenger side is controlled.

The air conditioning amplifier communicates with the servo through a communication/driver IC and wiring assembly called the air conditioning harness.

HINT:

Confirm that no mechanical problem is present because this DTC can be output when either a damper link or the damper is mechanically locked.

DTC Code

DTC Detection Condition

Trouble Area

B1441/41

Air mix damper position sensor value does not change even if air conditioning amplifier operates air mix control servo motor

  • Air mix control servo motor
  • Air conditioning harness
  • Air conditioning amplifier

WIRING DIAGRAM

PROCEDURE

1.

READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Operate the front passenger side temperature adjustment switch.

(e) Enter the following menus: Body Electrical / Air Conditioner / Data List.

(f) Check the value(s) by referring to the table below.

Air Conditioner

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Air Mix Servo Targ Pulse (P)

Passenger side air mix servo motor target pulse /

Min.: 0

Max.: 255

MAX. COLD: 105 (pulse)

MAX. HOT: 7 (pulse)

-

OK:

The display is as specified in the Normal Condition column.

Result

Result

Proceed to

NG

A

OK (When troubleshooting according to Problem Symptoms Table)

B

OK (When troubleshooting according to the DTC)

C

B

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

C

REPLACE AIR CONDITIONING AMPLIFIER

A

2.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

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

(e) Check the operation by referring to the table below.

Air Conditioner

Tester Display

Test Part

Control Range

Diagnostic Note

Air Mix Servo Targ Pulse (P)

Air mix servo motor pulse (P side)

Min.: 0, Max.: 255

-

OK:

Air temperature changes in accordance with each control range.

OK

REPLACE AIR CONDITIONING AMPLIFIER

NG

3.

INSPECT AIR MIX CONTROL SERVO MOTOR

(a) Replace the air mix control servo motor (See page 2016 MY Sienna [12/2015 - 08/2016]; HEATING / AIR CONDITIONING: FRONT AIR CONDITIONING UNIT: DISASSEMBLY ).

HINT:

Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or a known good one and check that the condition returns to normal.

(b) Check for the DTC.

Result

Result

Proceed to

DTC B1441/41 is output

A

DTC B1441/41 is not output

B

B

REPLACE AIR MIX CONTROL SERVO MOTOR

A

4.

INSPECT AIR CONDITIONING HARNESS

(a) Replace the air conditioning harness (See page 2016 MY Sienna [12/2015 - 08/2016]; HEATING / AIR CONDITIONING: FRONT AIR CONDITIONING UNIT: DISASSEMBLY ).

HINT:

Since the air conditioning harness cannot be inspected while it is removed from the vehicle, replace the air conditioning harness with a new or a known good one and check that the condition returns to normal.

(b) Check for the DTC.

Result

Result

Proceed to

DTC B1441/41 is output

A

DTC B1441/41 is not output

B

A

REPLACE AIR CONDITIONING AMPLIFIER

B

REPLACE AIR CONDITIONING HARNESS