plow not working.
fisher 8ft minute mount II
1999 f250 4x4
It sounds like you have a dirty power connection to the battery. Check the connections at the positive terminal of the battery, and wherever they attached the ground cable for the plow. One of them is probably loose or corroded.
As for the plow, check ALL the connections, battery, ground, etc. Be sure they are clean and tight. Plow should be grounded to the battery, not the frame.
Corrosion has an annoying way of getting into such things. You may also have a bad relay or solenoid. Go to the Fisher store and buy a spare, because they tend to fail in the middle of a storm, in the middle of the night.
Then check the studs on the plow pump and relays. Same deal, clean and tight. Apply Fluid Film to all of the above once it is working.



