A/C Intermittent Operation Due to Faulty Pressure Switch

To diagnose a faulty A/C pressure switch, verify the system refrigerant charge levels using a manifold gauge set. If the high and low side pressures are within the manufacturer's specified operating range, but the VCDS diagnostic tool indicates the pressure switch is signaling a 'shutoff' command to the ECU, the switch is likely providing false data. Confirm the electrical connection to the switch is secure and free of corrosion before concluding the switch itself is internally defective.