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A/C Signal: Description and Operation





A/C SIGNAL
This signal is sent from the A/C amplifier. The A/C amplifier outputs this signal to ECM when A/C ON conditions are satisfied on the A/C amplifier side. (The air conditioner does not turn ON in this state.) When ECM detects through the A/C signal that A/C ON conditions are satisfied on the A/C amplifier side, it uses the A/C signal as one of the factors to Output A/C ON signal and to control idle air control valve.





A/C SIGNAL OUTPUT FOR A/C AMPLIFIER
ECM outputs A/C ON signal (one of the signals for A/C amplifier to control the air conditioner) to A/C amplifier when A/C signal inputted to ECM and conditions listed below are satisfied.

Throttle valve opening : below 65°
Engine coolant temp. : below 110°C (230°F)
Engine speed between 700 r/min and 6,600 r/min.