Galant AWD L4-1997cc 2.0L DOHC Turbo (1991)
Compressor Clutch Relay: Description and Operation
Air Conditioning Circuit
When the driver turns on the A/C system, and the engine temperature is below 238° F, a positive voltage signal is supplied to the ECU (as an indication
that the A/C system is needed) and to one side of the A/C relay coil, located on the left fender apron near the firewall. The ECU determines if engine
conditions are suitable for A/C operation (idle speed, ignition timing and air/fuel mixture). If the ECU senses that conditions are suitable for A/C
operation, it supplies the ground circuit for the A/C relay coil, energizing it. This allows the relay to supply voltage to the compressor clutch.
