I would inspect, clean and adjust all of the contacts on the score reels. Also, manually operate the score reels with the machine powered off... Just press in the plunger on the solenoid/coil of the score reel and see if the reel will easily turn and "click" to the next number position. If the score reel doesn't turn properly, or is sluggish, you'll probably have to take the score reel apart and clean it... The grease that they used at the factory to lube the hub of the score reel can gum up over time and cause problems with the score reel operation...

There is only one "score motor" in the machine and it's located on the main board at the bottom of the main cabinet. You might be looking at the player unit in the the backbox. Yes, if the player unit is not operating properly, it can cause scoring and reset issues. You can manually operate the player unit to see if it advances and resets properly...

Not sure where we are at now... Maybe you can power off the machine, and then power it on again. Is the machine in tilt or game over mode? Then try to start a game. What happens when you press the start button?