Chevelle/Malibu V6-231 3.8L VIN A (1983)
A/C Signal: Description and Operation
Switch signals the Engine Control Module (ECM) when the A/C compressor clutch is engaged--12 volt sensed at ECM.
The ECM increases throttle opening--by actuating the Idle Speed Control (ISC) Motor--to compensate for the increase in engine load.
When the compressor clutch is disengaged, switch output voltage is 0 volts.
