Your only going to want to turn it back about a 1/8th of a turn. If that does not work, follow the wires and make sure they are all plugged in and not shorting out. If they wires are all OK, call me up and order a tack sending unit. Or you can order online.
https://parts.kenotractors.com/tack-sensor-old-style-p2178.aspx
https://parts.kenotractors.com/tack-sensor-new-style-p2177.aspx
There are the links for the two different types.
Feel free to give me a call if you need any help!
Tyler Nystrom
Keno Tractors
parts@kenotractors.com
866-363-8193
Phone hours: M-F 8am to 5:30pm PST Sat 9am to 1pm PST