The air mix door is automatically controlled so that in-vehicle temperature is maintained at a predetermined value by the temperature setting, ambient temperature, in-vehicle temperature and amount of sunload. SYSTEM OPERATION

- The A/C auto amp. receives data from each of the sensors.
- The A/C auto amp. sends air mix doors, mode door and intake door 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 A/C auto 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 A/C auto amp.

Door Motor Circuit
AIR MIX DOOR CONTROL SPECIFICATION

- The A/C auto amp. always automatically controls the temperature regardless of the operating condition of air conditioner when the ignition switch is ON.
- The A/C auto amp. performs the set temperature correction when the target temperature is set with the temperature control dial of the preset switch and decides the air mix door position.
- Based on the target air mix door position and the current air mix door position, it controls the air mixture door to always become the most suitable air mix door position.
- The air mix door is fixed to the full-cold position when the set temperature is set to 18.0°C (60°F) and it is fixed to the full-hot position when the set temperature is set to 32.0°C (90°F).