I was able to get a good deal on a Dr. Who pinball machine last weekend and couldn’t pass it up. Brought it home and the only issue it had, other than needing a good shop job, is that the left upper flipper was working when the game was going. It would fire in test mode but not during the game. Sometimes however, it would randomly start working (not sure what triggered it to work) and then would work as long as I didn’t power the machine off.

Then a couple days later I was playing and noticed that the captive ball popper would sometimes have issues not firing right away. I thought it might be a sensor that was going out or it wasn’t recognizing that the ball was there so the coil didn’t fire. All of a sudden the game turned on and then off. I immediately shut off the power. It turns out the plunger rod got stuck and wasn’t operating as it should because the spring was too weak. This game had been sitting for a couple years from what the guy said. I tried turning the game back on and there was only the topper lights and some random lights in the DMD that came back on.

I checked all the fuses and they checked fine. I noticed that the CPU lights were not on and I tested the 5v test point and got .19. Tested the 12v and got 12.03. Tested the 20v and couldn’t get a stable reading. If I moved my MM probe around on the test point it would give me random numbers between 8 and 19.

I’m new to pinball and trying to learn and understand the electronics side of things. Any advice would be helpful!

Unfortunately. None of that helped. Yes - I took the fuses out. I tested them both in the machine and out of the machine.

Not sure what you mean by “test points ok?” I tested them and noted that in my original post.

Forgive me if I don’t fully understand. Where do I start for checking wires? I checked all the connections on the boards but didn’t notice anything suspicious. What wires specifically should I check? What am I checking for exactly? No burnt connectors or loose connections.

I tried to reseat all the connection on all the boards. Same result. I’ll look over the wiki guide and try to work my way through what I understand. I’ll make sure and post the results.

Is it possible that the best solution is to just send the boards in to get serviced since they are old anyway?

I was able to follow the wiki guide on testing BR2. I got a 8.01 V reading. Which according to the wiki page, it should be 9 or slightly above. Could this be my problem then? I will add that it looks like it has been replace before.

I will read more of the wiki and what to test. A lot of good information there but definitely appreciate the input.

Unfortunately the wiki guide is more about when the game is resetting. So I’m not sure where to go from here. I took the board out to check for cold solder and couldn’t find any. It should be noted that BR2 and C5 looked to have been replaced at some point already. Any ideas on where to go from here to get the 5v power back?
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LTG How would I got about testing or fixing that?

What needs to be “stitched”? It looks pretty clean.

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LTG I put in the stitches and now I got 4.77 v on the 5v test point and the 5v LED turns on! Making progress. I do also get the 5v light on the CPU but that is it. No GI / no game boot / random dots on DMD. Seems like I don't have a stable enough 5v for everything to work?
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Any ideas on what to check to bring the 5volts back up to 5 volts?

chad I was trying each jumper that you suggested, step by step and then testing the board. I got down to the BR3 jumpers and turned on the machine to test and saw a spark. Running the jumpers from the AC leads on BR3 to pin 1 and 2 on J104 is the last jumpers I tried. I tested BR3 and it tested ok. I took all the jumpers off BR3

I took the machine to a local who works on pins and he reseated ALL ribbon cables and that fixed the issue. I did try kahr's daughter board but that didn't do the trick. Game runs great with or without the daughterboard now.