AIR MIX DOOR MOTOR

Description

SYSTEM DESCRIPTION

Component Parts

Air mix door control system components are:

• Front air control
• Air mix door motors (LCU)
• In-vehicle sensor
• Ambient sensor
• Sunload sensor
• Intake sensor

System Operation
The front air control receives data from each of the sensors. The front air control sends air mix door, mode door and intake door motor opening angle data to the air mix door motors LCU, mode door motor LCU and intake door motor LCU.
The air mix door motor, mode door motor and intake door motor read their respective signals according to the address signal. Opening angle indication signals received from the front air control and each of the motor position sensors are compared by the LCUs in each motor with the existing decision and opening angles. Subsequently, HOT/COLD or DEFROST/VENT or FRESH/RECIRCULATION operation is selected. The new selection data is returned to the front air control.

• Discharge air temperature does not change.
• Air mix door motor does not operate.

Inspection FLOW

1. CONFIRM SYMPTOM BY PERFORMING OPERATION CHECK - TEMPERATURE INCREASE

1. Turn the temperature control dial (LH) clockwise until 32°C (90°F) is displayed.
2. Check for hot air at discharge air outlets. >> GO TO 2

2. CONFIRM SYMPTOM BY PERFORMING OPERATION CHECK - TEMPERATURE DECREASE

1. Turn the temperature control dial (LH) counterclockwise until 18°C (60°F) is displayed.
2. Check for cold air at discharge air outlets. Can a symptom be duplicated?

YES >> GO TO 4
NO >> GO TO 3

3. PERFORM COMPLETE OPERATIONAL CHECK Perform a complete operational check and check for any symptoms. Refer to See: Initial Inspection and Diagnostic Overview\Inspection And Adjustment\Description And Conditions\Automatic Air Conditioner.

Is the Inspection result normal?
YES >> Refer to See: Symptom Related Diagnostic Procedures\Automatic Air Conditioner System\Symptom Matrix Chart.
NO >> System OK.

4. CHECK FOR SERVICE BULLETINS Check for any service bulletins.

>> GO TO 5

5. CHECK AIR MIX DOOR MOTOR OPERATION Check and verify air mix door mechanism for smooth operation.

Is the Inspection result normal?
YES >> GO TO 6
NO >> Repair as necessary.

6. CHECK LAN SYSTEM CIRCUIT Perform diagnostic procedure for the LAN system. Refer to See: LAN System Circuit\Automatic Air Conditioner.

Is the Inspection result normal?
YES >> GO TO 7
NO >> Repair as necessary.

7. CHECK AMBIENT SENSOR CIRCUIT Perform diagnostic procedure for the mode door motor. Refer to See: Mode Door\Automatic Air Conditioner.

Is the Inspection result normal?
YES >> GO TO 8
NO >> Repair as necessary.

8. CHECK IN-VEHICLE SENSOR CIRCUIT Perform diagnostic procedure for the in-vehicle sensor circuit. Refer to See: In-Vehicle Sensor\Diagnosis Procedure.

Is the Inspection result normal?
YES >> GO TO 9
NO >> Repair as necessary.

9. CHECK SUNLOAD SENSOR CIRCUIT Perform diagnostic procedure for the sunload sensor circuit. Refer to See: Sunload Sensor\Diagnosis Procedure.

Is the Inspection result normal?
YES >> GO TO 10
NO >> Repair as necessary.

10. CHECK INTAKE SENSOR CIRCUIT Perform diagnostic procedure for the intake sensor circuit. Refer to See: Intake Sensor\Diagnosis Procedure.

Is the Inspection result normal?
YES >> GO TO 11
NO >> Repair as necessary.

11. CHECK AIR MIX DOOR MOTOR PBR CIRCUIT Perform diagnostic procedure for the intake sensor circuit. Refer to "Diagnosis Procedure".

Is the Inspection result normal?
YES >> GO TO 12
NO >> Repair as necessary.

12. RECHECK FOR SYMPTOMS Perform a complete operational check and check for any symptoms. Refer to See: Initial Inspection and Diagnostic Overview\Inspection And Adjustment\Description And Conditions\Automatic Air Conditioner.

Does another symptom exist?
YES >> Repair as necessary.
NO >> Replace front air control. Refer to See: Control Module HVAC\Service and Repair.

DIAGNOSIS PROCEDURE FOR AIR MIX DOOR MOTOR
SYMPTOM: Discharge air temperature does not change.
Perform diagnosis procedure. Refer to See: LAN System Circuit\Automatic Air Conditioner.