Operation CHARM: Car repair manuals for everyone.

A/C High Pressure Switch Test

Before performing diagnosis of the A/C high pressure 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, further details on wire harness routing and retention, as well as pin-out and location views for the various wire harness connectors, splices and grounds.

1. Disconnect and isolate the negative battery cable.
2. Disconnect the wire harness connector from the A/C high pressure switch.
3. On the four terminal A/C high pressure switch, check for continuity between terminals C and D. On the two terminal A/C high pressure switch, check for continuity between both terminals of the switch. There should be continuity. If OK, test and repair the A/C high pressure switch sense circuit as required. If not OK, replace the switch.