A/C Clutch

When the ECM detects a signal from the air conditioner ECM that the air conditioner switch is turned on, the ECM outputs a signal to the magnetic clutch relay, turning it on.

The magnetic clutch operation is delayed about 0.5 second. During this time, the ECM opens the IAC valve to offset the drop in engine RPM due to the operation of the air conditioner compressor.

This system also helps maintain driveability by switching off magnetic compressor clutch when the vehicle is accelerated suddenly, or when engine is running under a heavy load condition.