With Electronic Automatic Temperature Control

An A/C pressure cut-off switch:
- is used to interrupt A/C compressor operation in event of high system discharge pressures.
- is located on the A/C manifold and tube between the A/C compressor and the A/C condenser core.
- has two sets of contacts. One electrical contact is normally closed.

The A/C pressure cut-off switch operates as follows:
- When compressor head pressure rises to approximately 2860-3068 kPa (414-445 psi), the contacts open and the compressor operation is shut off.
- When head pressure drops to approximately 1517-1930 kPa (220-280 psi), the contacts again close and allow operation or the A/C compressor.
- Shutting down compressor operation prior to the pressure relief valve set point of 3103 kPa (450 psi) makes sure the refrigerant is contained in the A/C system.

The switch contains a second set of normally open electrical contacts for the engine cooling fan motor.
- When discharge line pressure reaches approximately 2137-2344 kPa (310-340 psi), these contacts close and engage the engine cooling fan motor as override of the engine cooling system.
- When pressure drops to approximately 1896 kPa (275 psi), the contacts again open and the fan motor is disengaged. Fan control is returned to the powertrain control module.