Q8 drives solenoid 12 on PinBot.
Solenoid 12 is the playfield GI relay.
You'll need to find it under the PF and examine the relay and pin assembly for a short.
Makes sense. Good advice from your board guy.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

We can take care of you here. No need to contact the over worked Clive.
Post a pic of the relay with the connector removed. We can tell you which pins to test between. You need to measure resistance (ohms) of the relay's coil.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

Clive's been the best forever, the reason he is always overworked for weeks spells out the fact that he is the best. If your still looking for his help, simply, pick up the phone and talk to him. He will call you back. ~SpOoKy

No doubt that Clive could/would help...just taking the pressure off our bud.

The yellow cube is the relay.
It's soldered to the board at (Probably) 8 points.
2 of those points are the power and ground for the coil in the cube.
Those two points connect to two of the header pins.
We want to measure resistance between those two pins.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

Correct, the yellow wired one is the GI relay. No desoldering necessary. Just unscrew that GI Relay board from the underside of the PF. From there, the opposite side of the board will have the solder pads where the relay is soldered into. You can now directly probe those pads with your meter to test resistance on that relay to make sure it isn't burnt up. If you need instructions on how to do that, let us know.

Yup, probe those pins right on board. Nothing needs to be removed to check it. Test that diode out as well while you're at it.

No problem.

First inspect all the wires (6 of them) are connected securely. Next, those two pads that are more widely spaced apart are the coil section of the relay (to the right of the 6 pads that look like dice). With your meter set to OHMs, place one test lead on either side (color doesn't matter) and tell us what you get.

There is a diode on there as well that could be faulty, but you'd have to clip or desolder one end to test it out. Don't do this yet.

That is probably fine. At this point, you will want to check that diode. If the diode is shorted, it will definitely cause problems. I'm almost positive you will have to remove one end to test it properly, but try putting your meter in diode test mode and probing it like so:
03256-265.png

You should get .4-.6 in one direction and INF in the opposite direction. If you get 0 in both directions, there is definitely a problem, same goes for INF in both directions.

He is completely correct. I use Clive for all my board work, and he tested one board without issue, but told me to check my under pf switch. Yes you do have to do your own leg work sometimes as he cannot see underneath your game. Also those boards are generic for a generation of games, so he will not know exactly what it drives.

Looks like you are getting the great help from the forum though! That's what we/forum are here for, asking and answering. Glad you are getting dirty checking for things. It feels empowering once you do it a few times, and you can help others later!

Sucks waiting...I know! But knowing you won't blow anything on a freshly fixed board is worth the day or two wait

What's great about Clive is that he fixes the board, BUT also gives the warning too. Not everyone will do that. Some just return the "100% working board" without disclosure.

Props to Clive AND Chris Hibler.

I thought you had to desolder it to test it for sure...but someone should correct my "thought" on that.

If you're getting the same reading both ways, then something isn't correct (either the measurement method or the diode). It's probably the measurement method and I concur that you will probably need to desolder one end of the diode to test it otherwise the coil resistance will interfere.

Jaz

EDIT: You should get .4-.7V with the red on the anode (non-line) side and open, no reading or high-V (meter dependent) with the red on the cathode.

Test it once it is out to confirm your issues. Regardless, don't put that one back in. You'll need 1n400x diodes anyway if you own pinball machines. Might as well pick some up. Radioshack has them if you need them. Go with 1n4004 or 1n4007's. Only get 1n4001s if that is all they have.

Here is just one of my freaking crazy issue threads. I used a logic probe, had to test on some chips, boards and down to a diode on a coil

https://pinside.com/pinball/forum/topic/lwjp-switch-and-coil-issue

It may help when you have to troubleshoot down a transistor leg/matrix.

Not necessarily. Remove the diode, then OHM test those two points on the relay again. It should read the same value as before. Now put your meter in diode mode and test the removed diode. The failure mode of the diode will tell you what happened.

If it is reading INF in both directions, it means it is open, and it literally burnt up/overheated. Your relay coil is likely good (from your ohm reading), but the internal switch is probably seized, the relay needs to be replaced. I've seen this before on a DE MPU.

If it is reading 0 in both directions, then the cathode end of the diode received more than +35v for an extended period of time, or received a peak exceeding +50v, essentially turning it into a jumper. You would have to trace the wire(s) that connects to the cathode (striped end) and find out how high voltage got on there. The only thing that runs beyond +50v peak are coils, so look for bare GI wire/bulb sockets coming into contact with the coil lugs.

If the diode tests good, then you've got something else going on here under the PF. Again, the bare GI wire or a bulb socket touching a coil would do it.

While you are working on your GI, I would recommend checking your fuse values on all of your GI. I believe that they should be 5 amp slo-blo, but who knows what someone may have placed in there at some point--highest I ever saw was a 20 amp to replace a 5 amp, not even sure why that person bothered to replace it at all.

^^^^ Very good point here.

I just fixed a Comet that had the traces cooked off the power supply because of a shorted diode across the GI relay. Testing that is a good place to start.... so.... what they said.

Oh and don't try to use it without a good diode installed. The diode is there to protect transistor on your board from blowing out when the relay is turned off...

Jaz

P.S. GOOD POINT on the fuse check. It won't be the first time we've all seen over-fusing cause all kinds of problems...

I often forget to mention stuff like that to people new to electronics. I assume that they have checked that already because I automatically pull all fuses out of games I pick up and do the works before I even turn them on.

Fuses for the GI are not on the power board, look for four fuses mounted against the wall of the backbox on the lower right as you look inside the backbox.

this thread is what makes pinside great

this one is a nail biter though. is he going to find something? is he going to risk it? fingers crossed.

The switch lines don't carry the higher voltage. Just the lugs on the coils do, so nothing to worry about there.

So as CNKay said, there is a risk if you try to run the game as-is. Granted you reinstalled that diode on the relay board in the right direction, you CAN try firing the game up (with the PF propped up) and see if you can hear that relay clicking. If you hear any kind of buzzing or struggle on that relay, immediately turn the game off. If all is fine, put the game into diagnostics mode and run through the solenoid tests and make sure you don't hear anything like I mentioned on the relay. If I were you, I'd call Clive and just confirm this real quick.

Let 'er rip. You've done all the preliminaries correctly.
As posted above, listen and observe for abnormal events when you power up. You'll probably be OK. I can't think I of anything else you could do and if it were me, I'd power on at this point.

--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

AWesome! Glad you posted that it worked

I did it for Pinbot, not you.

You finally got your glass cherry popped.

Congrats!

Go into the diagnostics for the game and manually test all of the switches. Write down which ones aren't working and we'll help you get your switch matrix figured out.

The main ball trough switch is probably not working or not making contact, which is why it doesn't kick out the ball. That same switch is probably in the same line of the switch matrix as some of the spot targets.

Sorry about the glass. Did is scare the shit out of you with how loud it was?

I'm still a glass virgin, I'm dreading this.

Oh damn that is the second thread now with a shattered glass. So sorry to hear.

from your description it sounds like the Main Playfield glass is what shattered?
If so did you place it down on a cement (basement) floor? If so that is a no,no. There are all kinds of videos guys standing on glass, hitting with hammers forcefully and nothing but as soon as the edge is placed on cement and a tiny twist. Ka blewy!

its nasty when it happens. One minute its all good then BANG and theres glass from here to tuesday. You'll find bits of it 20-30feet away

Keep porcelain shards away from your pins!

Unfortunately it only takes touching the corner to a hard surface or a very sharp object just touching tempered glass to shatter it.