This didn't seem to be on their website anywhere, but it is the troubleshooting guide they distribute with new DYNA III kits. So if you inherited a bike that already had a DYNA III kit (that thing that doesn't look like points) you may need to reference this. These units are pretty rock solid, but occasionally they do go. Usually the electronic module is the thing to go, but occasionally the sensor plate will go. The reason for that is these bikes were designed wonderfully to keep water in the ignition area. If water sits in there for too long it can destroy the sensor plate. Drilling a small hole in the bottom of the case is one solution.