This is kinda urgent - as he's trying to get this machine to HAAG this coming Friday.
Can some of you EM gurus help him debug this?

i'm reaching out to folks and giving links to both threads...

Schematic?

Fighting reset it sounds like,check the playfield for a stuck switch.

Mine is now in pieces, do you have the ball in the trough to end the game before start up?
Are the score reels at zero and operating as they should?

Check the bonus stepper units and make they are all counting all the way to their staring point.

-scott

Good advice here. Both of these are the first place I'd check. Especially those score reels. I know you said you checked 'em but I've had to go over mine 3 or 4 times sometimes to get them working correct. They looked good but a 3rd cleaning of the 0 position got them going again. Stepper motor contacts are notorious as well.

Edit: I don't know how yours is set up but could that 100 relay be firing because it is trying to resest the 100 wheel on one of the scores?

Make sure your little coin switches are not stuck on.

The ball player unit should be incremented before the ball is kicked out. what happens if you manually increment the player unit 4 clicks while the ball is in the drain? I think the score motor should do that before kicking out the ball if you are playing a game with only one player.

On a Gottlieb 4 player the player unit activates the ball the in play. It's operation is somewhat controlled from the coin unit. The coin unit controls the amount of pulses the player unit gets to achieve the next ball in play depending on how many players are coined up. Not sure if Sonics work about the same. Your player unit looked like it may have been gummed up and sluggish. I think your player unit is going to activate a switch on your score motor to activate the ball return solenoid. If the player unit isn't functioning correctly or the switch on the score motor isn't gapped properly then that may be your issue. If it was me though and since it may be going to the show where it would be nice if it continued to run, I would go through everything, cleaning and gapping along the way. Sounds like there may be many little issues. The levers on the player unit and every other unit need to be free moving. The springs aren't strong enough keep them moving. Sometimes people grease them up and after many years that turns to crud and sticks it all up.

Wow the player stepper really looks like it could be your problem. If it isn't then it is it's own problem since you are having to push the disk manually to reset it. It should spin freely back to home not sit there till you put pressure on it like I saw on the end of the video. Unless that one is a single step back and somehow you put enough pressure to make it spin. I'm not the expert DirtFlipper or some of the other guys are as they are the ones that help me. Seeing the video tells me I would start with that stepper unit though.

Had a similar problem with a Triple Strike I just sold and found a wire had come off the bonus unit and the open close switch on the bonus unit was a bit out adjusted it problem solved

I posted on your main thread, but in addition, generally use you sand the brass out a little if absolutely necessary. Clay does speak to that in his guide which I linked in the other post. After watching your video ones more concerned that the unit wasn't completely clean.

In your video your reset bank is also kicking on repeatedly so whats the common.

Here is a snip of a Sonic Mars Trek which may be similar,compare to yours.
Sonic M-T a.JPG

Two things allow the reset bank coil to continually engage.

Sonic M-T reset.JPG

Follow the #3 coin re contact will close,that happens because a coin switch or the start button pressed too using that contact through the credit relay allowing that #3 relay to pull in.
The #3 coin contact completes the path then the reset re locks stays locked allowing the 1-2 & 3-4 reset relays which you see clicking via the impulse scr motor cams,meanwhile the score drums should zero out and the bonus contact should open @ zero to stop and allow reset to complete.

If the score drums zero and confirm there is a visible gap @ zero break then i would look at the bonus unit.
Most likely its a bonus unit contact zero contact thats not opening {why it keeps continually resetting]and not stepping up once to allow the sequence to finish and the ball to kick out.

I've heard some people use a hot iron and solder to fill in heavily worn brass rivets. I'd personally go that route before sanding anything. That way you're adding material not removing it. I imagine it would need to be periodically redone due to the soft lead solder.
Brasso works great to polish them, and the shoe surfaces.

I have and it works fine.

https://pinside.com/pinball/forum/topic/em-count-unit-wear-option#post-931875

First off, the stepper should index or spin back freely. Assuming the main spindle is not bound, I suggest you lube the pivot points with some Tri Flow Teflon lube. Get it in a 2iz squeeze bottle at a bike store and judiciously apply it with the tube to the pivot points and work them by hand until they free up. Or you can disassemble the complete unit.

The rivet heads can be built back up with solder. You will probably have to file them back down to a consistent profile.

I am not entirely certain if the player unit is really the root cause of the continued reset- especially if its sitting at its reset position and cannot really move.

I did have one question- your score reel looks really nice and clean... so I conclude you cleaned this and had it at least taken apart to have removed all the switch stacks and pull out the cam so you could clean it up. I have done this on a couple games, and its EASY to put it back together just slightly wrong and end up with issues. Does the score reel him position switch actually close and open correctly, the score reel is generating the pulses that are chattering your score reel switches to get them to move to zero and hold.... but if those switches are working, and its still pulsing, it could be the score reel cannot see the zero position. It could also be a few other things, as have been pointed out previously. But I would at least spend a good hour looking at the schematics and moving the score reel and watching the switch stacks open and close- very carefully. It is also possible to screw down a switch stack and have the screw INTERNALLY short to a switch blade (causing perhaps the same symptom as an out of adjustment switch).

Wish I had this game to help with the trouble shooting. It is MORE likely that you have a far simpler problem- but if your checking off those and things seem good- I would take a very close look at the zero position switch (home, whatever) on the score reel. If it does not know its completed a rotation (or 1/2 or however that switch sees the cams) its not going to stop.

After watching the video, I'm betting on one of the score reel zero switches being shorted closed when they should be open. I'm assuming the relay you pulled open to start the game was the reset relay. There are 16 to check and they could be shorted in the stack.

You just need to verify the switches that pin-it has highlighted above. It's going to turn out to be a really simple and obvious problem once you spot it. That's how it always goes.

Obviously the reset relay is not unlatching at the end of the start-up sequence. This must be because of a shorted switch.

And after seeing the video, I can see it is not the actual coin switch or the reset relay would snap back closed right away.

For what it's worth, I think you made the right choice.

Nothing wrong with taking your time and doing it right. It will be a showpiece once you've got it running and tuned. Now you can enjoy this last part as well.

i hear the dutch pinball guys (making TBL pin) just cancelled going to the Houston show 'cause the "clear pin" wasn't coming

I pictured this as unplayable and up on a rotating display like a prototype car at a car show. Doesn't need a 1000 fingerprints all over it.

I pictured it coming home with me

Thanks to all who are helping the OP. I can't wait to see this masterpiece finished.