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A/C Pressure Sensor (PCM Input)

Air Conditioning Pressure Switch
The A/C Pressure Switch (ACPSW) is used for additional A/C system pressure control. The ACPSW is also referred to as the Refrigerant Containment Switch.

For refrigerant containment control, the normally closed high pressure contacts open at a predetermined A/C head pressure. This turns off the A/C by opening the A/C demand circuit, preventing the A/C pressure from rising to a level that would open the A/C High Pressure Relief Valve.

The PCM modifies the shift scheduling when the A/C is on and the KOER On Demand and Cylinder Contribution Test (CCT) are aborted. An Excursion may be equipped with the optional Electronic Automatic Temperature Control (EATC).