Quoted from Fifty:
If I fully press down the rollover quickly the score reels don't move but I can hear the score motor rotating.
It sounds like the 1C score motor switch is doing it's job, but 2B (or in the circuitry) isn't doing it's job.
2B should be making from the beginning and opening after the 500/5,000 points have been scored..
I'd maybe recheck 2B score motor switch..