Clutch Cycling Pressure Switch
WARNING: This page is about a different car, the 1994 Mercury Grand Marquis and 1994 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
This switch prevents evaporator icing during normal A/C operation. Mounted on outlet side of evaporator, the switch controls current flow to compressor clutch relay.
The clutch cycling pressure switch also prevents compressor operation during cold weather. When ambient temperature is low, refrigerant pressure is also reduced. This opens pressure switch, preventing compressor operation. This low pressure feature also protects system when refrigerant level is low.