I was working on a Sonic Mars Trek this week and I had one problem with my bonus lights not lighting up on the playfield. I went to the bonus unit and just wiped down the contacts on the board and spider. No change. (this machine is in very good condition with very low play time) The contacts on the bonus unit looked perfect. So then I got out some metal polish and polished the contacts again and made sure the spider contact arms had good tension on the board contacts. No change. So this time I took the bonus unit, apart took spider out and tested with the continuity checker on my DVM all of the contacts on the end of the spider arms and none of them were making good contact with the arms! Hmmm ??? So I took a hammer and I Gently tapped down the rivets on the backside of the spider arms then tested again and got good contact. Put it all back together and it works perfect. My Question: is this situation common in EM games?
Do these contacts in these units (bonus, ball, player ect...) have this problem? Or is it just in the Sonic games?