This switch turns the radiator cooling fan on when the a/c system high side pressure reaches approximately 238 PSI. Air flow across the a/c condenser is imperative to prevent high side a/c pressures from causing system damage (blown hoses typically).When the a/c pressures go above 350 PSI so does the temperature of the refrigerant on the high side. The resulting temperatures can also damage compressor seals. The switch in the compressor is a normally open switch, at 238 PSI it closes latching the fan relay.
Electrical components such as switches are non-returnable parts.
Always refer to a factory service manual when diagnosing engine service problems. You can damage electrical components if the proper procedures are not followed. Be sure you are replacing the correct part.