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Automatic A/C

Circuit Description

The A/C control module receives input from the A/C sensors (for instance, photo sensor, ambient sensor, etc.) and controls the function of the air conditioning system. The A/C control module and various sensors provide accurate control of the air mixture using mode actuator, temperature actuator and intake actuator under all operating conditions.

The blower motor runs at the highest speed when the high blower relay coil energized through A/C control module. With the A/C switch ON, the engine control module(ECM) will ground the coil of the A/C control relay after a short delay to adjust idle speed. The function of the power transistor is that of the blower resister in manual A/C.