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A/C Signal: Description and Operation





This switch is installed on the automatic transmission. ECM detects transmission range by monitoring the ON/OFF signal from this switch and uses it as one of the signals to control the fuel injector, ISC actuator and automatic transmission.

ECM outputs A/C ON signal (one of the signals for A/C amplifier to control the air conditioning) to A/C amplifier when A/C signal inputted to ECM and conditions listed below are satisfied.
Throttle valve opening : below 60°
Engine coolant temp. : below 110°C (230°F)
Engine speed between 650 r/min and 5600 r/min.