I have to ask for some help for my Barracora which was working nicely until a few hours ago. I welcome everyone's comments.

Issue: The 3 pop bumpers, eject hole gate, 2 slings and both flippers are not working. They were fine until earlier today. This is a Williams System 7 machine.

What I have tried so far;
1- I went through the diagnostic procedures and noted the following - All digit displays are fine, all sounds from the sound board are fine, all lights light up nice and bright, all fuses were fine.
2- I tested the CPU diagnostics on the board and no problems noted.
3- The solenoid test worked fine for the first 16 steps then nothing for 17-22 which reflect in order - upper eject hole gate, left right and bottom pop bumpers, left and right kicker.
4- All touch switches for 10, 100, points or more work fine.

So basically anything that needed a coil to power it, stopped working. I could not see any wire breaks and everything is attached. There are some diodes but I do not know how to check these out (what part of the DMM dial do I use and what should I read?)

Ackk!

Fuse?  

Thanks Cooke and I did think about that like you and others have mentioned in other posts, check the fuses! I did not want to cry wolf  

I looked at the power supply board and replaced each fuse, one at a time with a new fuse - no change. There were 6 fuses.

I checked the fuse in the lower cabinet next to the transformer, changed that one as well, still no change.

I love these puzzles...now to solve it.

I'm no expert, but is there a fuse under the PF?  (you didn't mention that one)

I'm a little confused you said solenoid test 1-16 worked ok and also "anything that needed a coil to power it, stopped working". But 1-16 use coils too.

If you test again, are 1-16 still working? Depending on the order of your tests, it could be that the solenoid 17 coil went bad and blew a fuse.

Is there power at the 17-22 coils? You can test DC voltage with a DMM on either lug. Or you can briefly connect a jumper wire from the ground lug to any grounded metal in the machine. If the coil fires, this tells you to look on the ground side for problems. Next test might be to briefly connect a jumper wire from the tab of one of the solenoid transistors to ground (e.g. Q2 for solenoid 17 "Upper Eject Hole Gate").

Need to confirm ALLthe solenoid power is out. No coil operated functions working?

I have a spare driver board and MPU board newly shopped with new ROM's if it is a board issue.


My suspicion:

-Power board issue specifically high voltage section
-Connector issue
-Transformer at higher voltage (not too sure on this one, never dealt with transformer before)

Do you have schematics?

Does it boot up ok?

This Williams is different (no fuses under this pf) than the wedges that you and I also enjoy. I did go back and double check - twice just to be sure.

Quoted from tinyrodent

I'm a little confused you said solenoid test 1-16 worked ok and also "anything that needed a coil to power it, stopped working". But 1-16 use coils too.

If you test again, are 1-16 still working? Depending on the order of your tests, it could be that the solenoid 17 coil went bad and blew a fuse.

Is there power at the 17-22 coils? You can test DC voltage with a DMM on either lug. Or you can briefly connect a jumper wire from the ground lug to any grounded metal in the machine. If the coil fires, this tells you to look on the ground side for problems. Next test might be to briefly connect a jumper wire from the tab of one of the solenoid transistors to ground (e.g. Q2 for solenoid 17 "Upper Eject Hole Gate").

Thanks Tinyrodent.
I repeated the solenoid test 3x to be sure. The first 16 steps fire off no problem. Thanks for describing how to check with a dmm, I will get to work right away and see how that works before I try the other options.

Warren, if boards are ever needed, I will give you a shout for sure. Game boots and scores everything except the coil operated functions.

This is way too much fun! Ok, maybe not that much fun, but interesting nonetheless.  

sorry to hear.  its my old one and its never had issues beside one set of flippers acting up.  but that was just contacts.  hope it turns out to be a easy fix.  you have had it for alittle while now and nothing was acting up before?  at all?  strange science still going strong?

Obviously all the coil voltage is out. Source is transformer>Then to the power board on the lower right in your backbox>Then to the driver board.

If all else fails and its not a connector loose or broken high voltage wire to solenoids to under the playfield (which I doubt since the flippers and solenoids operate on a different circuit I am pretty sure), then its the power supply from the transformer or more likely the power board.

Check connectors are in contact first. If no solution:

Worst case scenario, remove the power board and send it out. I have so much experience with all I have done with my Barracora including getting all 5 boards completely rebuilt and then buying a second combo MPU and driver board set.

Ah, but I am not in Burlington.

If this doesnt resolve somehow, Rick I can try to help you out at some point when Im nearby.

You need to look at the sticker in the backbox that ID's the fuses and test the one for solenoids.

If connectors are OK here's your likely fix:

http://www.rottendog.us/WPS079.htm

Thank you Warren and Gory for the input. Work has been just nuts these past few days and I will get the chance to check things out on Sunday. I will go through everything step by step based on my skill level but I may need to look into getting some electrical help. I will keep you posted.

By the way Gory, Barracora and Strange Science are fantastic to play when 100%! Not to worry, pins need maintenance, that is normal. I am learning more and more each day which is why this hobby is so much fun for me.