Operation CHARM: Car repair manuals for everyone.

Air Mix Door Motor Circuit

Air Mix Door Motor Circuit

SYMPTOM
- Discharge air temperature does not change.
- Air mix door motor does not operate normally.

Inspection Flow:




INSPECTION FLOW

SYSTEM DESCRIPTION

Component Parts
Air mix door control system components are:
- Unified meter and A/C amp.
- Air mix door motor (LCU)
- A/C LAN system (PBR built-in mode 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 and intake door motor opening angle data to the air mix door motor LCUs, mode door motor LCU and intake door motor LCU.

The air mix door motors, mode 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 and FRE/REC operation is selected. The new selection data are returned to the unified meter and A/C amp.




Air Mix Door Control Specification

COMPONENT DESCRIPTION







Air Mix Door Motor
The air mix door motors are attached to the heater & cooling unit assembly. It rotates so that the air mix door is opened or closed to a position set by the unified meter and A/C amp. Motor rotation is then conveyed through a shaft and the air mix door position feedback is then sent to the unified meter and A/C amp. by PBR built-in air mix door motor.

DIAGNOSIS PROCEDURE FOR AIR MIX DOOR MOTOR
SYMPTOM: Discharge air temperature does not change.

Perform diagnosis procedure. Refer to ATC-64, "DIAGNOSIS PROCEDURE FOR LAN CIRCUIT". LAN System Circuit