I purchased a Night Moves a few months ago. Recently, my Night Moves table changed all of the scores and bookkeeping. Now all the high scores are 666 - 88,888,880 and the bookkeeping info is similarly filled with 8s. When I go into the bookkeeping and self test to set the info to 0, it doesn't work. The only selection that responds is "Average Playing Time", which produces the message "Bookkeeping cleared" when I hit credit/start, but it still keeps the average playing time as **.

Extra info, in case it helps: the memory test (and all other self tests) says everything is OK and Game Prom checksum matches expected value. Whoever owned it before me gutted the coin door mechanisms and added an add-a-credit button for free play. From what I can gather, Night Moves is basically a Gottlieb system 80B machine that was made by someone else (International Concepts). Apart from the high score / bookkeeping issue, the game works fine.

I just removed it, and checked the machine with the CMOS removed. It still had the old high scores and whatnot with it removed. When reseated, same deal. Would this confirm that the ram is bad? Is there any way to test it without buying another one?

Ordered a new 5101. I will update when / if it works.

No dice. After replacing the 5101, it still has the same issue.

After a couple of weeks of leaving it unplugged, it zeroed out. I'm guessing that's because the battery died. Afterwards, it kept high scores and records correctly, but the next time I tried resetting the scores, everything was again set to 666 - 88,888,880. Given that the ROM tests are coming up with the right checksum, I'm pretty much at a loss for what's causing the problem.