My Paragon has exhibited a strange behavior a couple of times this week. Wednesday I was playing a one player game. During ball two the machine just spontaneously switched to ball three with the ball still in play. There was no bonus collection. Subsequent games were normal. Last night, during a two player game with my wife, the game spontaneously switched from player one to player two while she still had a ball in play. Again, there was no bonus collection. It just started racking up points on the second player while she continued to play her original ball. I haven’t seen this behavior before and thought I would ask if someone here has come across this and how they addressed it. Many thanks for any suggestions!

My first thoughts went to the trough as well, but the no bonus thing is a head scratcher. I haven’t had a chance to open it up yet, but will check that switch and connectors first.

I’ve had the game for years. It’s an original MPU. I replaced the rectifier board with a new one from GPE, rebuilt the connectors, and re-pinned when I first got the game. I switched out the battery for a capacitor a few years ago. There is a daughter card in-line on the MPU that supports the X-Pin 7volution displays. But again, these have also been in service for several years, and no recent changes.

I’ll start at the trough and move back from there. I’ll post what I find.

Thanks!

I realize that it is not a mechanical unit advancing, I just wanted to convey the sense of what happened. I don’t think it tilted, the flippers stayed engaged, and it was pretty seamless. I can’t say for certain on the drops resetting. Something called my attention to the event, so maybe. I’m certain on the bonus not being applied. During the one player game where I first saw this behavior I was one shot shy of Super Bonus, and was pissed that I didn’t get the score and the bonus hold over.

I took a quick pass at this. The trough switch looks like it is gapped correctly, and nothing seems out of the ordinary on visual inspection. I did clean the switch with a business card and alcohol. I played five games without the error recurring. I used a plastic spudger to trip each of the various tilt switches with a game in play and the ball in the shooter lane. They all behaved as expected.

Nevertheless, I think the suggestion of a phantom tilt is a likely culprit. I will pay attention for the drops resetting if and when this recurs. The cap on the tilt bob looks like the factory original, and we all know how flakey Bally caps can be. I may proactively replace it and the switch diodes on all of the tilt switches if the problem comes back. Does that seem like a reasonable next step?

Thanks again for all of the input.