As a guess, it sounds like the ball count stepper is counting up, as it should on reset, but not counting back down - as it should.

The coin relay is responsible for the ball count step up.
Look for either a stuck coin switch or the coin relay "D" not (gapped closed) opening is where I would look first.
1 Wms Klondike coin re..JPG

Seen on schematic snips the coin relay and contacts completing path to ball count s.u.2 Wms. Sch. Klondike coin re..JPG

3 Wms Klondike sch..JPG

There is a guy in Cando that is a EM wiz. I could maybe get your his info if you want.

My Williams Triple Action was doing the same thing. It was a stuck scoring switch on the playfield. Dunno how it was related, but as soon as I fixed that switch my problem went away.

Type in Klondike and have a look at the old threads from me, Pafasa and Skybug...they're the threads with 100's of posts from a year or so ago. There was heaps covered about the stepper units for Klondike.
The 2 things that I had issue with regarding ball count apart from the stepper was the game over / tilt relay right at the back of the cabinet(the double decker switches). Those little suckers get out of adjustment and can cause ball count problems. Also on the last set of impulse switches on the score motor(towards the rear and the lowest switches), they also give you the ball count and you'll see those 5 notches on the cog that represent each ball so you could check that to see if that's working right when you press start.
I think someone might have included a schematic with one of the posts also.
Good luck getting her going!

Dirty wiper unit, it can't find the end switch on the fifth or third ball location.
Clean the wiper unit and fingers, lube it with a extremely thin layer of light oil.
Check the tension of the wiper fingers on the unit, do they touch the disc?
Lots of times these (stepper) units are causing the problem.

I never file on contacts on wiper units, cleaning is in most cases enough to get it running again.
In every manual from Williams there is a page that says: "overlubricating is much more worse then underlubricating".
So if it works with no lube on the wiper unit it must be okay also.
Check the tension of the switches on the wiper also, maybe one of them is not making enough contact.

Milton, just catching up on this thread.

If you look at the bit of schematic that Pin-it posted and the fact that you are stepping up to position 9 on the ball count unit (remember there is also a zero position 10 in all). I’m suspecting the coin RE is not de – energising at the right time. The Coin Relay needs to de energise after the first cycle of the score motor which is 180 degrees. Check all the switches under the Coin RE coil, one of them may be keeping the Coin RE energised after the first cycle.

** Also check the SW on the score motor (3D) responsible for de energising the Coin RE coil (3 ball/game mode), in fact I would check this one first. If you are in 5 ball per game mode, than it is the SW on the index cam (below the SW In my bit of schematic)**

help.jpg

_{Post edited by Chrisbee: Little more info added (3 ball v 5 ball)}

One thing you can be sure of, your EM will not be suffering a virus attack.

Does the score reels reset, when you press start button?

I'm not great at reading schematics but that game over relay at the back right of the cabinet can be a pain...did you check the double decker switches on that?

On the ball count stepper, can you manually advance it 9 places (ball 9) until the metal disc reaches the flattened section? Then can you push the other coil plunger and get it back to where the little lug on the metal cog makes contact with the switches?(0 ball, game over) I thought maybe it wasn't counting down all the way to 0 so then it starts counting back up too far. On my Skylab, if I press the button twice it counts up to 9 but I'm not sure that's relevant to your issue. Sometimes that metal cog can be spun right round the wrong way and be in the entirely wrong place. I just had to adjust the spring tension on my stepper as it wouldn't count up smoothly. I adjusted the main spring so it was turned 4 times and then had to check that each spring had enough recoil to move the metal rods. I hope some of this makes sense and helps.

That too is a function of the Coin RE though the Ball count unit "when at zero position".
spend a bit of time making sure the Coin RE is all good, coil and contacts ETC.