Operation CHARM: Car repair manuals for everyone.

A/C Signal: Description and Operation





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 ISC actuator and fuel injection respectively.





AIR CONDITIONING (A/C) ON SIGNAL OUTPUT FOR A/C AMPLIFIER (VEHICLE WITH A/C ONLY)
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 60°
Engine coolant temp. : below 110°C (230°F)
Engine speed : between 650 r/min and 6000 r/min. (1.0 liter engine model) or 5600 r/min (1.3 liter engine model)