Game works fine during play, match, attract mode etc., but noticed now if I power off and on again, the match number always comes up '17'. Also the number of credits can change to a way different number than it was before. But other things seem to store okay when turned off/on like the last game score, high score to date etc. I tried clearing every setting using the button on the MPU but no change. Do I need to clear something else some other way? Why would it only goof up some settings and not others?

More observations, the match might also display '27' sometimes, and it also does this just from a reboot when I exit the settings with the inner door button. So is the '17' normal for just Lightning or any similar-era Stern game? I can't seem to get the credits to go wacky now, perhaps it was only during the first time I'd powered it up yesterday in a few weeks and the battery was just totally drained... but all the score thresholds I'd set many months ago have always been saved correctly.

Okay, I guess I don't really have an issue then. The occasional '27' is still weird but, oh well. I'll doublecheck the battery voltage, it is an original Stern board. My mind is really going, had this game bout 20 years and I never paid attention to that odd '17'. Thanks everybody!

I don't believe so, it's only 17 or 27 on powerup or reboot. Matches show fine at end of game and all the displays show correctly during play, the diagnostics and the display tests. I just turned it on three times in a row, got one 17 and two 27s. Can't get the credits to change anymore. Great, now the '27' is beginning to bug the HELL outta me! I think the credit issue was my fault with the wrong coin switch setting and didn't notice it was adding a ton of credits instead of only one.