D50/Ram 50 L4-2350cc 2.4L SOHC (1992)
Compressor Clutch Relay: Description and Operation
Air Conditioning Circuit
LOCATION
The A/C relay is located on the left fender apron near the firewall.
PURPOSE
The Air Conditioning Relay supplies current to the A/C compressor clutch when the ECU determines that engine conditions are suitable for A/C
operation.
OPERATION
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. 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.
