A/C Pressure Switches

The A/C system is protected by two pressure switches. The A/C high pressure switch interrupts the A/C request signal when the A/C line pressures climb above 2826 kPa (410 psi). The A/C low pressure switch interrupts the A/C low pressure switch signal when the A/C line pressure fall below 207 kPa (30 psi). When the PCM sees an open in either signal, the A/C clutch relay control circuit is no longer grounded, thus shutting off the compressor. When high side pressures drop back down between 1034-1724 kPa (150-250 psi), the PCM will allow the A/C compressor to operate.