My brother and I just picked up a beautiful specimen of Solar Ride. It is a Gottlieb Sys 1. When we got it the displays were out and low and behold it was only a fuse. However the fuse is only half the problem. When turning the game on sometimes the displays don't come on at all. Sometimes they come on but I'll notice the balls in play light and credit lights are stuck at 00 and don't change when credit is added. Upon pushing the start button the displays light up all character lines from their default of 0s. The third option is they come on and the game works fine. The board looks like it has been replaced by a previous owner and I've noticed some solder missing off the battery mod he did. I'm thinking I have some bad solder somewhere else he might have done. What controls the displays? Am I on the right track?

Funny you should bring this topic back.
Just a week or so ago we just simply changed out the battery holder that was on the game when we purchased it for a new one.
Now the game remembers credits and shows them in the credit window.
However it refuses to show the high score to date or the matching numbers at the end of a game.
When the game goes to show the high score to date the top left dmd is just completely blank, as is the match display window.
But very happy that the game now remembers credits as that was the biggest issue.