Vacuum Switch

Disconnect wire connector. Disconnect vacuum line and attach vacuum pump. Using an ohmmeter, check for continuity between wire terminals. With no vacuum applied, continuity should be present. With 6-8 in. Hg applied, no continuity should exist. Increase vacuum to 9 in. Hg and slowly release vacuum. Continuity should exist when vacuum reaches 5.5-6.2 in. Hg.