Grand Cherokee 2WD V8-4.7L VIN N (2000)
High Pressure Sensor / Switch: Description and Operation
HIGH PRESSURE SWITCH
The high pressure switch is located on the discharge line or discharge line block fitting near the compressor. The switch is screwed onto a fitting
that contains a Schrader-type valve, which allows the switch to be serviced without discharging the refrigerant system. The discharge line fitting is
equipped with an O-ring to seal the switch connection.
The high pressure switch is connected in series electrically with the low pressure switch between ground and the Powertrain Control Module
(PCM). The switch contacts open and close causing the PCM to turn the compressor clutch on and off. This prevents compressor operation when
the discharge line pressure approaches high levels.
The high pressure switch contacts are open when the discharge line pressure rises above 3100 - 3375 kPa (450 - 490 psi). The switch contacts will
close when the discharge line pressure drops to 1860 - 2275 kPa (270 - 330 psi).
The high pressure switch is a factory-calibrated unit. The switch cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.
