Continental V8-4.6L DOHC VIN V (1998)
Refrigerant Pressure Sensor / Switch: Description and Operation
A/C Pressure Switch
The A/C cycling switch is mounted on a Schrader valve-type fitting on the top of the suction accumulator/drier.
^
A valve depressor, located inside the threaded end of the A/C cycling switch, presses in on the Schrader valve stem.
^
This allows the suction pressure inside the suction accumulator/drier to control the operation of the A/C cycling switch.
^
The electrical switch contacts open when the suction pressure drops to 152-193 kPa (22-28 psi).
^
The contacts close when the suction pressure rises to 276-324 kPa (40-47 psi).
^
When the A/C cycling switch contacts close, the signal to energize the A/C clutch is sent to the Powertrain Control Module (PCM).
^
When the A/C cycling switch contacts open, the A/C clutch field coil is deenergized and compressor operation stops.
^
The A/C cycling switch will control the A/C evaporator core pressure at a point where the plate/fin surface temperature will be maintained slightly
above freezing.
^
This prevents icing of the A/C evaporator core and blockage of airflow.
^
It is not necessary to discharge and recover the refrigerant system to remove the A/C cycling switch.
