Minn Kota Help

I have a Minn Kota bow mount that lately has been shorting out. It will work for a while and then just stop. I usually run around with the power level at 2, and I will switch to 3 or 4 in windy conditions. When it stops, if I turn it to 5 it kicks in and I can go right back to 2 and it will work again for a while. Every time it stops I bump it up to 5 and have no problems. Anybody have any idea whats going on?

I have one that did the same. had to have the brushes polished. warranty covered the work. works correctly now