Main Relay

1. Disconnect battery ground cable, the remove relay box cover and relay (RDI FAN MAIN).
2. Using an ohmmeter, check that there is continuity between terminals 3 and 5.
3. Check that there is continuity between terminals 2 and 4.
4. Check that there is no continuity between terminals 1 and 4.
5. Apply voltage across terminals 3 and 5:
a. Check that there is no continuity between terminals 2 and 4.
b. Check that there is continuity between terminals 1 and 2.
6. Reverse procedure to install.