Quoted from Carl_Hungus:Thanks guys.
I noticed the top and lower targets light to follow the three lanes above, but the middle doesn’t. How can I tell if it’s a bulb vs an electrical connection between the lane and the target?
My number 5 when lit doesn’t move to 6 when the ball rolls over it. Is there a fix for this?
The first very basic things to try is a) replacing the bulb with a known working one (if the new bulb works, the old bulb is just dead), and then b) try wiggling the bulb a little and see if it flickers on and off (this would mean the light socket is not making great connection.) If you still aren't getting anywhere with that, I'd try hitting the target manually when the light should be on to see if you are getting the extra points and sequence, which might give you an idea what you are dealing with.
Underneath the playfield, the switch under #5 has two contacts - one is to give points and one is to advance the sequence if appropriate. Both should connect when the ball goes over it. Make sure the contacts are making solid connection when the ball goes over it, that they are clean, etc.