If this is simply a blown fuse, you should not need to take the controller in for service. The fuse will be located somewhere near the wiring terminal, possibly behind a faceplate on the control box. You will be looking for a glass tube. If the wire inside the glass tube is broken, the fuse is blown. Simply snap the fuse out, take it to a local hardware store, get a new fuse and snap it back in. If the wire inside the glass tube is not broken, it is possible that the circuit board is fried. Check the fuse first. If you don't want to do it yourself, a Hunter dealer can check and change a fuse no problem, but its going to cost you. Simple fix for a DIY.
Tony Posey
Ridge Run Landscapes