Hey I'm restoring a Back to the Future machine. Almost done and turned it on but I have 2 problems currently that I can't find help too anywhere.
1st problem deals with the Alphanumeric Board. The previous owner added a new rottendog board to the game and it is still relatively new but when the game turns on, the board only partially works with like every letter or number or symbol is only partially brought up and not the whole letter or word.
2nd problem, so when turned in the game will start and play all correctly, even with the display problem, but when the first ball locks for multiball, it won't eject the 2nd ball onto the playfield to continue playing. It will just sit there and wait until it starts running through all the test switches and eject the 1st ball back onto the playfield. I thought about doing a switch test to see if there was any problem with the switches but I can't navigate the service menu cause the display is all jumbled.
I kind of think that the problem deals with my MPU but I'm not sure. It boots correctly and its not bringing up any problems with the PIA, blanking, or +5 Leds. I've replaced the batteries, looked all over the board for problems or damage but I can't seem to find any, and I'm kind of wondering if I just have a bad chip somewhere in the board or whatnot. Any help or ideas would be appreciated!

Okay that fixed the display problem! That was a simple fix! But my multiball is still not working right though!

Its showing that all the lock switches are working correctly. So I'm looking into checking the ball trough switches to see if there's a problem there.

Also I forgot to mention, my plan is to take the batteries out and go with a NVRAM chip in n the board to avoid acid accidents.

Nevermind! I found the first ball locks switch wasn't going off with the ball hitting it so I tweaked it and its at 100%