This is a replacement Thermistor AKA as a Current Inrush Limiter.
This is found in the On/Off power box located to the right inside the coin door.
Does you came constantly reset when both flippers are pushed?
Well 70% of the time it’s this little device causing the issue; as it’s just worn out!
To determine if it’s the culprit, unplug your pin, unscrew the power box, and cut one leg of this device off.
Depending on the game, inside the power box, there may be two round disc devices, if there is a “red” one, don’t cut it, that is a Varistor AKA as a surge protector.
The Thermister is usually “black”, or “Grey” in color.
Now re-mount your power box, and try your game.
If it has stop shutting off, then this was your problem. Yes, you can run your game without it, BUT replace it now, or you will greatly shorten the life of other electronic components, that are likely already very old.:)
The thermistor is installed in the power box of Williams/Bally WPC System pinball machines in series with the black power line wire.