Yes, it could well be as simple as a switch that is not adjusted correctly - maybe it doesn't even need replacing!
It will be well worth your while to become 'close' to the machine and what makes it tick as you are very likely to have more issues down the track and it's a bit silly to call someone around (probably for >$100 each time) when you could probably learn how to fix most problems yourself.
+1
Should be a simple fix - Adjust the switch and you should be fine. Check that there is no loose wire on that switch as well.
Or a dry joint - it's amazing how many things on a pinball machine you can fix by resoldering!
