Last Modified: 11-29-2007 1.6 C
Service Category: Vehicle Interior Section: Heating/Air Conditioning
Model Year: 2008 Model: Sequoia Doc ID: RM000002ZTE002X
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DESCRIPTION (2008 Sequoia)

DTC

B1445/45

Passenger Side Cool Air Bypass Damper Control

DESCRIPTION

The cool air bypass damper servo sends pulse signals to inform the air conditioning amplifier of the damper position. The air conditioning amplifier activates the motor (normal, reverse) based on the signals to move the cool air bypass damper servo to any position. As a result, when the air conditioner is operating, the temperature of the air blowing toward the passenger's head area is controlled.

HINT:

  • Although the Techstream title says "Passenger Side", there is only one cool air bypass servo motor on this vehicle.
  • Confirm that no mechanical problem is present because this diagnostic trouble code can be output when either a damper link or damper is mechanically locked.

DTC Code

DTC Detection Condition

Trouble Area

B1445/45

Cool air bypass servo motor position sensor value does not change even if air conditioning amplifier operates cool air bypass servo motor
  • Cool air bypass damper servo
  • Air conditioning harness
  • Air conditioning amplifier

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1.

PERFORM ACTIVE TEST USING TECHSTREAM (COOL AIR BYPASS PULSE)

(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 Electrical / Air Conditioner / Active Test / Cool Air Bypass Pulse.

(e) While performing the Active Test, confirm that the air blown from the front center and front side registers changes in temperature.

Air Conditioner

Tester Display

Test Part

Control Range

Diagnostic Note

Cool Air Bypass Pulse

Cool air bypass servo motor

Min.: 0

Max.: 255

-

OK:

Air temperature changes in response to the operation of the cool air bypass servo motor.

Result

Result

Proceed to

NG

A

OK (When troubleshooting according to Problem Symptoms Table)

B

OK (When troubleshooting according to the DTC output)

C
A

4.

REPLACE COOL AIR BYPASS DAMPER SERVO (for Passenger Side)

(a) Temporarily replace the cool air bypass damper servo with a new one HEATING / AIR CONDITIONING: FRONT AIR CONDITIONING UNIT: DISASSEMBLY (2008 Sequoia) .

HINT:

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

NEXT

5.

CHECK FOR DTC

(a) Clear the DTC HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DTC CHECK / CLEAR (2008 Sequoia) .

(b) Check for DTC HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DTC CHECK / CLEAR (2008 Sequoia) .

OK:

DTC is not output.

OK

7.

REPAIR OR REPLACE AIR CONDITIONING HARNESS

(a) Repair or replace the air conditioning harness HEATING / AIR CONDITIONING: FRONT AIR CONDITIONING UNIT: DISASSEMBLY (2008 Sequoia) .

NEXT

8.

CHECK FOR DTC

(a) Clear the DTC HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DTC CHECK / CLEAR (2008 Sequoia) .

(b) Check for DTC again HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DTC CHECK / CLEAR (2008 Sequoia) .

OK:

DTC is not output.

OK