RAM 2500 Truck 4WD V10-8.0L VIN W (1997)
High Pressure Sensor / Switch: Description and Operation
Fig 25 High Pressure Cut-off Switch -- Typical
HIGH PRESSURE CUT-OFF SWITCH
The high pressure cut-off switch is located on the discharge line near the compressor. This switch is connected in series between the low pressure
clutch cycling switch and the Powertrain Control Module (PCM). This switch prevents compressor operation when the discharge line pressure
approaches high levels.
When the discharge line pressure rises above 3100 to 3375 kPa (450 to 490 psi) the switch contacts open and interrupt the A/C request signal
circuit to the PCM. The PCM responds by de-energizing the compressor clutch relay, which will cause the compressor clutch to disengage. The
switch will close again when the pressure drops to 1860 to 2275 kPa (270 to 330 psi).
The high pressure cut-off switch is a factory-calibrated unit. The switch cannot be adjusted or repaired and, if faulty or damaged, it must be
replaced.
