Escape 4WD L4-2.5L Hybrid (2009)
High Pressure Sensor / Switch: Description and Operation
Air Conditioning (A/C) High Pressure Switch
The A/C high pressure switch is used for additional A/C system pressure control. For refrigerant containment control, the normally closed high pressure
contacts open at a predetermined A/C pressure. This results in the A/C turning off, preventing the A/C pressure from rising to a level that would open the
A/C high pressure relief valve.
For fan control, the normally open medium pressure contacts close at a predetermined A/C pressure. This grounds the ACPSW circuit input to the PCM.
The PCM then turns on the high speed fan to help reduce the pressure.