Not sure what everyone else is doing for New Years... I am working on this Bally!
First post, long time lurker of Pinside. Bought earlier in the year. Someone has been pestering me to get it working properly.
Problem: Scores reels do not activate/work. No sound either
Flippers/bumpers all activate and are nice and responsive. Play field lights up, bonus score lights work, and activate randomly when you roll over certain parts of play field. All good stuff.

I have full schematic and Bally's EM 1946-1976 guide book.
No idea how to read schematics(Guess I'll be learning yahoo)
If I try to manually change the score reel(Any of them) then power off the machine, then on again. It will not reset the score reel therefore not allowing
play.
Previous owner had zero insight as to history and any work done on it. He had it in his office for 22years.

Any thoughts on where to start?

Looks like coin operation has been bypassed.
Main on/off switch on bottom of machine(had three wires connected before) Green is still connected.
Blue and Yellow are wired together.
When you plug the machine in, you hit the credit button on the coin op panel. and game play can start.