Hi everyone,

I have repaired many SS pins right down to board components, but I do not have any experience on an EM. I have an electrical technician background, but it is only used on pinball machines.

I need some help. I bought a train wreck of an EM and I am troubleshooting it, but not having done this before it would be nice to hear some second opinions and some general "Yes, you are doing it right" or "No, you are doing that wrong" from others with more knowledge than me.

I am using pinrepair, and I have the schematic from PBR.

When I plug in the pin the backbox lights up and so do the coin door lights. That is pretty much it. The primary fuse holder was a corroded mess, as was the fuse so I replaced both. The line cord was also a mess so I have replaced it, but the readings are still off. According to the schematics I should be seeing 25V for the coils and 6V for the lamps. I'm only seeing 4V at the 10A fuse holders (LIGHTS) and 14V at the 15A fuse holder (coils). So I went back to the transformer and I am not seeing 25V from any tab on the transformer. Here are my readings. I am using my black lead on the ground lug.

ab0632958c1fc5cd16c295d61bf6d11f85147d6e (resized).jpg

I'm also getting 4V from another lug (LIGHTS) on the opposite side of the transformer (not shown in the picture).

As you can see the transformer is a mess but I've seen worse. Is there anything else I should be checking? A switch that deactivates high power?

Thank you. I am not use to working with AC as is probably very obvious.

Measuring from the common lug to START I am reading 30V. From common to HIGH I am reading 32V. I am also reading 6.5V to the backside of the transformer now that I am using the proper return. Everything on the transformer checks out. Thank you.

Moving onwards, when I power up the machine, I get backbox lights and coin door lights. What should be the next sequence of events?

Start button doesn't do anything. It is wired. I'll verify the wiring with the schematic.

I see the coin chute switches. When I activate either switch nothing happens. There are 15 credits already on the counter. I don't know how long they have been there.

I am going to check the tilt/drop/slam switches as well. I am guessing they should be normally open, but I'll verify with the schematic.

The credit unit is the cleanest bit of the pin. It is not binding and counts up/down without any issues. There is a lead through the zero position. Here is what it looks like with 0 credits;

20181111_200941 (resized).jpg

After I add a credit it looks like this. The switches are still all closed.

20181111_200958 (resized).jpg

I am not sure how to start a the score motor by hand.

I left the credit counter at 2. Powered up the pin. Tried hitting start again for the hell of it (nothing happened). I rotated the score motor counter-clockwise by hand. It did not start rotating on it's own. I will check to see that it is getting voltage. How easily should it rotate?

[EDIT] I found the pinwiki with examples of how the credit unit is supposed to look with zero, greater than zero, and max credits. I'll make sure to adjust the switches to match.

[EDIT2] Does the playfield need to be installed? It would be easier to troubleshoot this with it out of the way. I don't see why it would be needed right now.

I'm at work right now (Eastern Standard Time) but I'll verify the 25V is getting through the fuse to the motor.

pinhead52 Okay, so I'm happy to report a little progress. I managed to get the score motor to rotate. I took out my DMM and checked the connectivity of the bounce switch and the anti-cheat switch. I had no connectivity through the bounce switch even though I could see it was closed. I took some 1000 grit sandpaper I had and ran it over the contact points a few times. I did the same to the anti-cheat. I powered up the pin an was able to move the score motor. The score reels are all at zero now. There is a pretty loud buzz coming from inside the cabinet. It seems to be emanating from a relay marked V.

Pressing the START button still doesn't do anything. I also tried added a few credits and this did not work either.

The relay is labelled V but I don't think it is from this machine. It is in position Q.

20181112_214738 (resized).jpg

There is also a relay labelled W in position U.

When I turn the game on, relay Q and U lock on right away. These are the GAME OVER and 1st BALL relays.

This game is a pretty big mess as you can see by the wiring. Two of the relays have even been replaced with modern electromechanical relays.

I will definitely be cleaning up the steppers as I can already see some are sticking but I want to make sure the pin is able to go through its normal start-up sequence before I do any of this. I'll will avoid using anything flammable.

I'm trying to avoid creating new problems for myself until I'm more familiar with the start-up sequence. Right now, I can't even start a game.

Odd, you'd think it would be reverse so that the 1st ball relay was energized only when the ball was in the shooter lane. Saves punishing the relay the entire time the pin is on.

Game over looks a little crispy. Upon closer inspection the label is definitely burned. I'm more concerned that these relays are not the correct ones. How do I know this relay will even work? Has the proper number of switches?

I am having difficulties reading the schematics. Some areas are easy to read, and other areas confuse me. For example, the Game Over relay (Q) I can see it on the schematics, but it's not clear to me which switches on the relay should be open or closed. I figured the switches would be grouped on the schematic for ease of use but they are spread out.

I'll just have to get use to the way everything is laid out.

Looks like I need a A-9740 and a A-9736 then. I'll see if I can get one locally. If not, I'll put in a PBR order.

Thanks guys. I'm going through this website constantly. I'm also part of pinballninja so I've been watch a slew of new videos on EM repairs.

Slow and steady...

There is some obvious crud on the player unit that I am going to clean off but I am going to take my time with it. In the meantime, this thread will go quiet, and I'll place an order for those new coils from PBR.

Hang tight everyone and thanks for the help so far!

pinhead52 I cleaned the player stepper unit and it is rotating properly now. I think someone used 3 in 1 oil and it created a gummed up mess in some areas. I've cleaned everything with degreaser and then isopropyl alcohol and bought some clear synthetic silicone grease to re-lube things a bit.

I managed to borrow two coils for game over and the 1st ball, but I'm do not think my coils are bad. When I turn the game on I can see the coils are energizing. That tells me they are fine.

With credits on the machine, pressing start still does nothing. I am able to manually move the score motor and it completes the rotation on it's own.

I am not sure where to go from here. Do I first work on the credit switches and try to figure out why they are not adding credits to the machine or do I ignore this and continue to manually add the credits and try to figure out why the game won't start?

HowardR I just want to make sure I am understanding the terminology being used here. Being new to EM's I am not clear on some of the lingo. When you say REPLAY BUTTON are you just talking about the START BUTTON? I just want to be sure we are talking about the same thing here.

I will try the jumper wires. I had not gotten to section 3 of pinrepair yet. I'm only at section 2j. I'll read ahead a bit.

HowardR Mopar pinhead52 Okay guys, I had a little time tonight.

If I manually activate the Start Relay (S), the machine does not do anything.

I have not tried using alligator clip wires yet as I can't seem to find mine. I blame myself for leaving out my electronic toolbox with my kids in the room.

I have bigger problems it seems. I mentioned this pin was a mess right?

Here are my Replay Button relay (V) and Tilt Hold relay (H). I have no way of testing these new electromechanical relays, nor do I hear them energizing or de-energizing.

20181120_200929 (resized).jpg

Add to that...

A previous owner took the original V and H relays in this pin and relocated them to Q and U. The original Q and U are nowhere to be found.
20181120_200949 (resized).jpg

Ignoring the new electromechanical V and H relays for the time-being, are the original V and H relays compatible to Q and U? I need to confirm that V and H have the proper switch stacks, number of switches, and whether the switches are open, closed, or make-break. I need to confirm the coil strengths as well. This is going to be a pain in the ass.

I will need help confirming things. I'm getting better at reading these schematics, but I'll need affirmation from anyone willing.

Is it possible to buy original relays from PBR with the proper switch stacks pre-installed? I would like to remove the new electromechanical relays and revert everything back to the way it was from the factory.

Ah, I didn't see the 'contacts' area. So for Q (AG-9740), there are 3 contacts. 2A, 2B, 1C. I don't see any legend stating A=open, B=closed? Is it on the schematic somewhere or is this just a standard that I was not aware of?

So just for my own reference...

Q is 3 contacts. Open, Closed, Make-Break
U is 3 contacts. Open, Closed, Make-Break
V is 1 contact. Open
H is 3 contacts. Open, Closed, Make-Break

So I could swap U and H and get that relay back where is belongs. My V does have 5 wires connected to it. Hmm... The schematic shows it should only be 1 contact. Why are 5 wires connected to it?

Thank you for this. The schematic has been driving me nuts. It confuses the hell out of me. Shit is spread out everywhere. For example, I just want to trace the wires coming off the Q coil. I should have black on one side of the coil providing 25V and BL+BLK on the other side, but I don't. I have two black on one side of the coil and a short solid blue wire that goes to one of the switches in the stack on Q. The short blue wire isn't on the schematics that I can see. Only then do I have the BL+BLK wire that heads over to the score motor 4C. To me, they missed a switch.

Reading this now http://www.pinrepair.com/em/index3.htm#schematic

I had not read ahead this far, but it seems I should as I am missing key items in the schematics.

Thank you.

I appreciate all the help guys.

Q, U, V and H. Photos of these would be great. Thanks!

The first photo is perfect. I can make out the colours no problem. The rest are in yellow lighting so it's tough to make out the colours. I can see the switches though so that's a start! Thank you!