The biggest killer of PGM's by far, is the poor maintenance of the RC Valves. Cables that are too tight, or gummed/coked up valve components put unnecessary strain on the servo motor, which then burns out the PGM.

The best and safest option is to see if you can try YOUR PGM on a known working bike. If that bike fails to start, then you have instantly found the issue, and can then work on why it has failed. If you try another PGM on your bike without finding the cause of the failure, it could be a very expensive couple of seconds!