Operation CHARM: Car repair manuals for everyone.

High Pressure Sensor / Switch: Testing and Inspection

Before performing diagnosis of the high pressure cut-off switch, verify that the refrigerant system has the correct refrigerant charge.


For circuit descriptions and diagrams, refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.
1. Disconnect and isolate the battery negative cable.
2. Unplug the wire harness connector from the high pressure cut-off switch on the refrigerant system fittings.
3. Check for continuity between the two terminals of the high pressure cut-off switch. There should be continuity. If OK, test and repair the A/C switch sense circuit as required. If not OK, replace the faulty switch.