From Newsgroup: rec.games.pinball

I have a new to me WMS BK2000.
Fired it up and it boots. But when I try to use
the diagnostic buttons, to set adjustments,
it goes into a loop yes-no/yes-no/yes-no rinse and repeat.

SO, I thought the advance button was stuck down.
Nope. Very clean. BUT, there's a diode soldered
across two of the pins?? Never seen this before on
any machine. Actually appears to be factory installed.
Regardless, I unsoldered one end of the diode.
No change in behavior. So, some questions:

1) Is this factory/normal?
2) If so, what's it for?
3) Has anyone seen a setup like this before?
4) Since it's apparently NOT the problem, any
suggestions/advice/ideas on why it goes into a loop?

BTW, If I get through the whole sequence of adjustments,
the game appears to go into attract mode. But the coin drops
aren't working so I can't put credits onto it.

Thanks for any insight.
Ron Kral
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