It's hard to say from the video. If you manually put a score on all the reels, knock down a few targets and put a ball in the out hole, then press the replay button, what happens? Or better yet, what doesn't happen that should?

/Mark

The replay/start button on the front of the cabinet. What I'm trying to understand is what doesn't work when you start the game normally.

The Game Over relay is an interlock relay (with two coils) that can hold it's last position (latched or tripped) with no power. I think it's the only interlock relay in the game. If your Game Over relay is stuck in the wrong position that might explain what you're seeing. If you manually flip it to the other position and press the start button does anything change?

When would it click? Your video doesn't seem to show it changing.

Your game isn't dead. Some things are working. But to figure out why it won't reset it would help to know if anything changes when you start a game with the Game Over relay in one position compared to the other position.
Old Chicago Game Over relay (resized).jpg
If you press gently where the red "Trip" arrow shows the Game Over interlock relay should snap into the Trip position. If you push where the "Latch" arrow shows it should snap back into the Latch position. Try it and you'll see that all the switches change position too. Is there any difference when you start a new game with the Game Over interlock relay in the Latch position (shown in the photo) compared to when you start a game with the relay in the Trip position?

Those both sound ok. What's more interesting is what's not working.

This time can you try the experiment and start from the same place both times? Try this:
1. Shut the game off
2. Press the Latch side of the Game Over relay
3. Add a score to the score reels and drop a few targets
4. Turn on the power and start a game
5. Does it reset the score and drop targets and serve up a ball?

Now repeat everything except this time press the Trip side of the Game Over relay in step 2.
Does it reset the score and drop targets and serve up a ball if the Trip side of the Game Over relay is pressed in first?

Saucers will often work whenever the game is turned on so the ball returns to the outhole. Pop bumpers and flippers don't need to do that since they can't trap the ball like a saucer can.

Does the bonus reset if you start a game with the trip side pushed in on the Game Over relay?

There's a stepper that hangs from the playfield right near the flippers that is probably the Bonus stepper. (Is there a label on it to confirm that?) The stepper has two solenoids: one to take a step forward to advance the bonus and the other to take a step backward while counting down the bonus.

Shut the power off and see if that stepper can move forward and backward easily by pushing in the solenoid plungers and letting go. If that looks good leave the stepper somewhere in the middle (not at zero) and start a new game with the Game Over relay in the trip position. The scores should reset and the Bonus stepper should step down to zero.

It could be that your game is stuck in the middle of reset because the Bonus stepper isn't resetting.

I just got an Old Chicago, also has startup issues as well, but looking at your pictures I am fairly certain mine looks the same with wires like that, I was also wondering if it was normal but based on what you and I seem to have I am guessing yes. Probably a common harness for a few games that they just adapted

All I get is backglass lights right now, my center kickout hole just keeps kicking, and the score motor just keeps running. Fairly certain my ball count stepper and bonus stepper are completely greased up and messing with things.

Scores are not at zero I will give that a shot. I checked the kickout hole switch and it isn't stuck. I too have bought a game that I assumed had blown GI fuse or connector issue and instead every bulb was just bad, funny how that can happen. I have a friend who has offered to help me out on it and he recently helped me with another Bally EM so I am most likely going to take him up on it and learn from him more. Otherwise my backglass and playfield are in amazing shape so hopefully it cleans up nicely here.

Ok, so your bonus stepper seems to be basically working.

To sort out why the drop targets won't reset you need to diagnose the circuit on the left:
Old Chicago Drop Target reset (resized).jpg
Shut the power off, set your meter to the lowest resistance setting and clip your meter probes where the red arrows show. Then manually rotate the Scrore Motor until the Score Motor 12A switch at the top of the schematic closes. The 12A switch is probably on the end cam, furthest from the score motor, at the bottom of the switch stack. But you'll want to compare the wire color against the schematic.

With the score motor switch closed, manually close the Targets Down relay, Out Hole relay and Game Over relay one at a time. Each time you close one of those relays, you should see the resistance between the probes drop to an ohm or less indicating that the switches have closed. If you can't get any of the three relays to give you a low resistance reading move the probes to either side of the score motor switch to make sure that it is closed.

Another thing to sort out is why the Out Hole kicker won't fire, on the right side of the schematic. You said that when you had a bonus and you put a ball in the Out Hole that the bonus counted down. That tells me that the Out Bonus Score relay in the schematic fired. When you close the Out Hole switch does the Out Hole relay fire (after the bonus has counted down)? If not, diagnose the red circuit for the Out Hole relay. It may be that the Bonus Unit Zero Make/Break switch isn't working properly.

Edit: I overlooked the two switches below the Out Hole relay coil on he Game Over and Reset relays. Those too should be in red and need to be working.

Have you checked out the Out Hole relay circuit in reply #21?

Kicking the ball from the outhole to the shooter lane is the last thing that needs to happen after everything else has reset at the start of a game, or after the end of a ball. Until you have the earlier stuff sorted out there's little point in trying to figure out why the later stuff isn't working. It might work just fine once you fix the earlier problems. Same thing with the flipper power - fix the stuff that has to happen before the flippers and they might just start working.

In general you may find that things will go more smoothly and be easier to understand if you focus on one or two problems at a time rather than poking around and wondering about the whole game. That applies to cleaning, adjusting, modifying, etc. too.

Seems a little high, but let's go with it. What about the Out Hole relay circuit? The Out Hole relay not firing is probably why your drop targets aren't resetting.

So through the Score Motor 1C switch, the Bonus Unit Zero switch and the Out Bonus Score relay switch you can measure 1.2 ohms when all the switches are closed? That'd be good. What about the last two switches in that circuit on the Game Over relay and Reset relay?

Please read this through a couple of times to make sure it makes sense. Ask for clarification if it doesn't.

Let me back up to make sure we're on the same page. We're working on the theory that the Out Hole relay isn't firing during reset. For it to fire as expected 5 switches in the game (in red) must close to complete the circuit so that current can flow through the Out Hole relay coil and fire the relay:
Old Chicago Out Hole relay (resized).jpg
We need to figure out why you're apparently not getting the closed circuit that sends current through the relay coil. It could either be that the switches aren't all closing properly, or that the relays and motors that close them aren't working properly or there could be a bad connection somewhere between them.

The first step is to figure out if you can get a closed circuit through the entire circuit. One way to do that is to use a multimeter with the power off and work your way through the circuit. Clip one probe to the 30 (yellow) wire on the Score Motor 1C switch and leave it there. Clip the other probe to the 43 (green-yellow) wire on the other side of the Score Motor switch at position 1 in the drawing. Then turn the Score Motor if necessary to close the switch and you should get a reading of an ohm or so across the switch. If not, the switch isn't making good contact and may need to be cleaned or adjusted.

Once the Score Motor switch is good, move the probe from position 1 to position 2 and repeat the experiment, this time with two switches and the wiring between them being tested. With both switches closed you should still read about an ohm of resistance.

Then move to position 3 and check for about an ohm of resistance when all three switches are closed.

You're working your way through the circuit towards position 6 in the drawing. It's a little like the "Can you hear me now?" cell phone commercials.

Note that when you get to position 4 your resistance reading will jump from about an ohm to about 50 ohms because the Out Hole relay coil itself is in the circuit you're testing and that coil has a resistance of about 49 ohms as shown on the schematic. So positions 4, 5 and 6 should all read about 50 ohms when all of the switches are closed.

If you're lucky, somewhere between position 1 and position 6 you'll find a switch that isn't closing properly and needs cleaning or adjustment. That might be all it takes to get the Out Hole relay to fire.

If you can get all the way to position 6 and close all the switches and see a total resistance of about 50 ohms, that says that the switches and wiring are good and that we need to figure out which of the relays or score motor that close those switches isn't doing the right thing.

Don't worry too much about the resistance value of the coil. You can't reliably measure its resistance unless you desolder one tab because there may be other things wired in parallel with it. What's important is the resistance of all the switches and wiring in addition to the coil. So if your coil measures 21 ohms or whatever by itself and the entire circuit from the yellow wire to position 6 is just an ohm or so more when all the switches are closed I'd call the circuit good. Then we'd need to figure out which of those switches isn't closing during reset.

If you want to be sure that the coil can fire you could try to jumper from the yellow wire directly to the solder lug with the blue-white wire, and jumper from the other solder lug to the wire at position 6. That would connect the coil directly to the power rails with no switches. If the coil is good it will fire when you turn the power on.

Sounds like your switches on the Game Over relay aren't making good contact.

The first step might be to have a close look at the Game Over relay switch that needs to close to get the Outhole relay to fire: red-white wire to yellow-black wire, or position 5 on the schematic in reply #34. When switches on a relay close, the contact on the longer blade should move and touch the contact on the shorter blade, and then keep going a little further to just push the shorter blade back a bit. That's called over travel and gives the contacts a rubbing motion against each other that helps them clean each other. Check that you have a little over travel on the switch by the time the white plastic armature clicks into its locked position. It sounds like maybe you only have over travel if you press the armature in further than it goes on its own.

The other thing to try is to gently clean the contacts by putting something between the contact points when the switch is closed and gently pulling it out. Try a dollar bill or business card first. If that doesn't help try a flexstone or some really fine (1000+) sand paper.

If cleaning the contacts doesn't help then carefully try adjusting that switch so it closes with a little over travel. You'll want to use a contact adjuster or really fine needle nose pliers. Most other tools have a better chance of making things worse.

I just saw your cry for ‘haaaaalp.’ NicoVolta has sold me on the ‘Magic Brush’ method:

1. Clean contacts with Q-Tip and 91% Isopropyl alcohol.
2. Polish to a bright shine with a Dremel tool and a #443 brush.
3. Repeat step 1.

I can pay you a visit and show you how it works with my Dremel tool.

Before you do anything, you need to remove the Trip/Latch relay from the mech board and tighten the screws that go through the Bakelite spacers. I always forget this step! I looked at the picture again and it looks like you can get to those screws without having to remove the relay. You usually aren’t so lucky.

After tightening screws and cleaning the contacts, the leaf switches should be straightened, then adjusted to properly align the leaf switches in the armature slots and properly gap the contacts. You know you have it right when one leaf switch causes the other leaf switch to move or ‘deflect’ when the armature is moved. Deflection is good.

One ‘fly in the ointment.’ The trip/latch may need adjustment. If it clicks when latching or unlatching then it is probably okay. Best not to mess with this adjustment until you learn exactly how to do it.

I might have missed something.

Edit: MarkG does a better job, above, than I did explaining ‘deflection.’

There is one more rule that I follow. Never take a switch stack apart unless one of the leaf switches is broken or a contact is missing.