Remember there is a ground (separate wire, or through the frame of the module) that connects to the engine frame, and also a kill wire that goes to the stop switch. If you *don't* ground the ground it won't fire, and if you *do* ground the kill wire it won't fire.
If there is a ground wire and it has become detached, you have to reconnect it properly. I haven't seen how it is constructed, so I can't guess whether it can be repaired.
