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Air Conditioning (A/C) High Pressure Switch

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.