My golf trolley controller only goes to 4 would that be a problem with the board ?
IF it has stopped going up any higher in speed then it most likely will be the speed control switch in the handle . (see photo) . This speed switch if it gets a knock or bumped i.e. when packing away, normally it becomes erratic in scrolling the speeds. So it can jam at any speed or not move at all, or move and jump to say speed 6 straight from 0. The controller governs the speed displayed in the handle (circuit PCB) but the speed switch alters the speed itself. Hope this makes it a bit clearer.