B1446

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1446/46: Air Mix Damper Control Servo Motor Circuit (Driver Side)

DTC B1446/46 - Air Mix Damper Control Servo Motor Circuit (Driver Side)

DESCRIPTION

The air mix damper servo (for driver side) 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 air mix damper (for driver side) to any position. As a result, the amount of air that has passed through the evaporator and is now passing through the heater core is adjusted, and the temperature of the air blowing toward the driver side is controlled.

HINT: 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.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (AIR MIX SERVO TARG PULSE (D))
(a) Connect the Techstream to DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Air Conditioner / Data List / Air Mix Servo Targ Pulse (D).
(e) According to the display on the Techstream, read the Data List.

Air Conditioner





OK:
The display is as specified in the normal condition.

Result





C -- REPLACE AIR CONDITIONING AMPLIFIER
B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.

2. REPLACE COOLING UNIT DAMPER SERVO SUB-ASSEMBLY (AIR MIX DAMPER SERVO (for Driver Side))
(a) Temporarily replace the cooling unit damper servo sub-assembly (air mix damper servo) with a new one Disassembly.

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 -- Continue to next step.

3. CHECK FOR DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Check for DTC Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC is not output.

NG -- REPAIR OR REPLACE AIR CONDITIONING HARNESS
OK -- END (AIR MIX DAMPER SERVO IS DEFECTIVE)
4. REPAIR OR REPLACE AIR CONDITIONING HARNESS
(a) Repair or replace the air conditioning harness Disassembly.
NEXT -- Continue to next step.

5. CHECK FOR DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Check for DTC again Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC is not output.

NG -- REPLACE AIR CONDITIONING AMPLIFIER
OK -- END