When I first got my Stern Jurassic Park the right coin door switch would sometimes just eat coins, they'd go through perfectly fine, it wasn't the mech, they'd just go past the switch, trigger it fine, but the switch wouldn't register them. I didn't have a replacement switch so I just covered up that coin slot since the other worked perfectly fine. Now about a year and a half later it started happening with the other coin slot, and started happening with the left ramp too.

Is there something that would be causing all these switches to only work intermittently? I presume it's still possible they're all just individually bad, it would just surprise me a bit. They register about 90% of the time, and fail the other 10%. I would normally check the switch matrix and see if they're all on the same wire or something, but I haven't really looked into how this new Spike system for that works with all the separate boards and such.

Also for what it's worth I've never been able to recreate the switch registration failure in the switch test--probably like 50-100 tests of dropping a coin through the coin switch and 50-100 tests of rolling a ball past the left ramp and I have 100% success rate with both, but that might just a be a result of me not testing enough.

Will try that now, thanks! Also correction, the left ramp switch is an opto not a microswitch, my mistake, was a week ago that I was looking at it and I had forgotten.

Tried reseating the connectors for the coin door switches, no luck, still failures when inserting coins. I'll try the ramp opto next.

Alright went back to the mentioned connector to look closer at the pins, they were indeed a bit loose and pressing them in seems to have worked. Testing on the opto is going fine as well, but it's faked me out before, so if there's more issues I'll report back but for now things look good.

Thanks!

Okay update on the opto, after much succesful testing I tried it out in game, had one shot fail to register out of 25 or so, so perhaps didn't get that one. I had a little more trouble tracking where the wires go out of this one though, there's one immediate connector which I checked out, but then after that I couldn't particularly see where it went, so I might've gotten the wrong thing.

Update: A few more games and another failure on the left ramp, so for sure still issues there

Still no luck on the ramp opto. Seems like when I put a slow ball past it in testing it works 100% of the time, no issue, but a fast ball in game has around a 10% failure rate.

Just to update this thread in case anyone is stumbling on it through a web search of a similar problem, I posted this issue on the Jurassic Park club thread and was recommended a fix, link to that here - https://pinside.com/pinball/forum/topic/jurassic-park-stern-2019-owners-club-welcome-to-jurassic-park/page/240#post-6576599

The issue was opto misalignment, it is apparently a common problem in that spot. Putting a piece of tape that covers the bottom half of the hole in the ramp cut for that opto fixed it for me.