Mode Door Motor Circuit

TROUBLE DIAGNOSIS


Mode Door Motor Circuit


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

INSPECTION FLOW











SYSTEM DESCRIPTION

Component Parts

Mode door control system components are:
- Unified meter and A/C amp.
- Mode door motor (LCU)
- A/C LAN system (PBR built-in mode door motor, upper ventilator door motor, air mix door motor and intake door motor)
- In-vehicle sensor
- Ambient sensor
- Sunload sensor
- Intake sensor

System Operation
- The unified meter and A/C amp. receives data from each of the sensors. The unified meter and A/C amp. sends air mix door, mode door, upper ventilator door and intake door opening angle data to the air mix door motor LCUs, mode door motor LCUs, upper ventilator door motor LCU and intake door motor LCU.
- The air mix door motors, mode door motors, upper ventilator door motor and intake door motor read their respective signals according to the address signal. Opening angle indication signals received from the unified meter and A/C amp. and each of the motor position sensors are compared by the LCUs in each door motor with the existing decision and opening angles.
- Subsequently, HOT/COLD, DEF/VENT, OPEN/SHUT and FRE/REC operation is selected. The new selection data are returned to the unified meter and A/C amp.






Mode Door Control Specification





Mode position can be selected manually by pressing MODE switch or DEF switch of the preset switch. This enables to fix a mode position. Automatic control by unified meter and A/C amp. Pressing
AUTO switch allows automatic control by unified meter and A/C amp. During the automatic control of mode position, a mode door position (VENT, B/L, FOOT, or D/F) is selected based on a target air mix door opening angle and sunload depending on a temperature calculated by unified meter and A/C amp. In addition, D/F is selected to prevent windshield fogging only when ambient temperature is extremely low with mode position FOOT.

COMPONENT DESCRIPTION

Mode Door Motor





The mode door motors are attached to the heater & cooling unit assembly. It rotates so that air is discharged from the outlet set by the unified meter and A/C amp. Motor rotation is conveyed to a link which activates the mode door.

DIAGNOSIS PROCEDURE FOR MODE DOOR MOTOR





SYMPTOM: Mode door motor does not operate normally.
Perform diagnosis procedure. LAN System Circuit.