Mode Door Motor Circuit

TROUBLE DIAGNOSIS

Mode Door Motor Circuit

- Air outlet does not change.
- Mode door motor does not operate normally.

INSPECTION FLOW


1. CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - DISCHARGE AIR

1.Turn mode dial to all five positions.
2.Confirm that discharge air comes out according to the air distribution table. Discharge Air Flow.
Can a symptom be duplicated?
YES- GO TO 3.
NO- GO TO 2.

2. PERFORM COMPLETE OPERATIONAL CHECK

Perform a complete operational check and check for any symptoms. Operational Check.
Can a symptom be duplicated?
YES- How To Perform Trouble Diagnosis For Quick And Accurate Repair.
NO- System OK.

3. CHECK FOR SERVICE BULLETINS

Check for any service bulletins.
- GO TO 4.

4. CHECK MODE DOOR OPERATION

Check and verify mode door mechanism for smooth operation in each mode.
OK or NG
OK- GO TO 5.
NG- Repair as necessary.

5. CHECK LAN SYSTEM CIRCUIT

Perform diagnostic procedure for the LAN system. LAN System Circuit.
OK or NG
OK- If the symptom still exists, perform a complete operational check. Operational Check. If no other symptom exists replace front air control. Service and Repair.
NG- Repair as necessary.

SYSTEM DESCRIPTION

Component Parts
- Front air control
- Mode door motor (LCU)
System Operation
The front air control receives signals from its various dials and switches. The front air control then sends air mix door, mode door and intake door motor opening angle data to the air mix door motor LCU, mode door motor LCU and intake door motor LCU.
The mode door motor reads 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 LCU's 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.






COMPONENT DESCRIPTION

Mode Door Motor





The mode door motor (1) is attached to the heater and cooling unit assembly. It rotates so that air is discharged from the outlet set by the front air control. Motor rotation is conveyed to a link which activates the mode door.

DIAGNOSTIC PROCEDURE

SYMPTOM: Mode door motor and/or air mix door motor does not operate normally.
Perform diagnostic procedure for LAN system circuit. LAN System Circuit.