I have a Centaur II and the transistor that controls the outhole kicker keeps shorting and the coil locks on. I have replaced the transistor numerous times along with the coil, driving diode, driving resistor, and the U1 driving chip. But the transistor will keep shorting and locking the coil on after about 10 games. It only happens on this one transistor. I have checked to make sure the coil is not shorting against anything. When the transistor shorts out it still tests good with a MM but after replacing the transistor it fixes the issue for about 10 games. Any idea what would cause this?

I'll do that. Thanks for the tip Lloyd. Your always very helpful.

Thanks for the additional tips. And the more I think about Lloyd's answer I don't think a crack in the trace would lock the coil on. I would think that would keep it from energizing and not cause it to lock on. But Lloyd is a lot smarter than me about these things so I'll still check it out along with the other tips. Thanks again.