So I'm close to wrapping up my restoration and while tweaking switches and such, the game started resetting in attract mode. Boards were serviced by Clive. First power on everything was great. Also, when the Martian coils go off in the game it resets but in coil test it doesn't. Where to start?

I'll check voltages but most of the wiki assumes faulty boards or diodes. The boards were completely serviced and a connections are fresh. Additionally, it is resetting in attract without hitting both flippers. I was hoping there was somewhere to start looking assuming the boards are rebuilt.

So I'm a moron with a dmm but the service outlet reads 120v. The part where I get confused on my dmm is when testing tp102, the voltages jump all over the place. From OL, to 5v-16v. Never settling on a reading. I'm not sure if I have my dmm set wrong or what. Additionally, when I got the game, the secondary inturupter was not plugged in. I plugged it in. I'm not sure if that could be the cause or not but I thought I should mention it. Whatever the issue is, it seems to be degrading and getting worse. One last piece of info, though I don't think it matters is Clive put a remote battery holder on the board but I haven't put batteries in it but I that shouldn't matter.

Thanks man. I'll get it figured out eventually. I'm certain it's something simple I'm overlooking. I'll start with the most simple and obvious things first.

So, the first thing out of the gate I checked may be the culprit. I removed the j103 connector and didn't have a single reset in nearly 10 minutes of being powered on. Would a grounded light socket cause resetting? By taking the gi out of the loop, my resetting stopped. As stated before, Clive at coinop cauldron serviced the boards and the j103 connector was replaced/upgraded. image.jpgimage.jpg

Thanks for the replies. I'll be home shortly and will investigate further. I have a sneaking suspicion what it might be.

So tp2 is solid above 5v when j103 isn't connected

Tp2 below 5v with j103 connected

Resetting and readings as it happens with j103 connected. Then j103 disconnected and voltage stabilizes with no restarts.

Pic of service box volts at molex plug.
image.jpg

Where do I look next. I swear it seems like something is shorted/grounded out. As for the rest of the wiki; I know the driver board is securely grounded, all components tested and suspect ones replaced.

One other question. I want to see what the voltages are coming off j103. Where do put the common probe (on the ground braid?) to test the pins?

So I did as Herg suggested and disconnected all power to the bill ung kit. I played nearly 10 minutes without a reset. Now where to look?

Thanks for the reply. Pin 32 of the game rom resulted in 5.2v

So I added the main ung board and played several games totaling roughly 10 minutes with no reset. Added the expansion board into the loop and the resets returned. I'm not sure where to head next.

I'm pretty sure I have it narrowed down to the ung expansion board. Yes I have reached out to him. At any rate, hopefully someone might have any ideas or suggestions.

Test reading with bill ung expansion board hooked up and the reading at the game rom pin 32. Reading below 5v

Test reading without bill ung expansion board hooked up and the reading at the game rom pin 32. Reading below rock solid above 5v

Ha. Yeah that was me. LOL. That ended up being the diodes on the driver board. This is something different.

So I took a long video showing the 5v reading to show the fluctuations. At roughly the 3:13 mark (of course just as I pan to the boards. Oh and my apologies for my daughter yelling for the wet dog to get of the couch) the game resets in attract mode. Both bill ung boards are plugged in.

Additionally, I threw in a a kahr 5v daughter board (not for this video) and all resetting went away even with both ung boards in place. I also reseated the little rom carrier with the yellow wire attached to it on the main ung board which didn't prevent resetting. Any ideas?!?

So I double checked the voltages between tp101 and pin 32 on the game rom without either bill ung board powered up. The reading was 5.09v on both tp101 and pin 32. No loss of voltage between the two.

With one bill ung board powered on, The reading was 5.09v on both tp101 and pin 32. No loss of voltage between the two.

With both bill ung boards powered on, The readings are unstable, jumping from 5.07 down to the 4.8's on both tp101 and pin 32. Can't determine loss of voltage between the two.

I spoke with bill ung who pinned the issue on the driver board. When I told him Clive rebuilt it and showed him what was done as well as the videos showing the readings told me maybe Clive has a suggestion because he doesn't. Any help would be appreciated. I have went step by step on the wiki and without the boards everything is great. With only one ung board, everything is great. Both boards not so great.

Any help?

Thank you for the reply. Unfortunately I don't have another driver board. I would be disappointed if that truly was how the board was serviced. Without a doubt, when the Ung boards aren't hooked up (or just one board), the game is a solid 5.07v. There is no loss of volts across tp101 to the game rom pin 32 either. So if as you say, it shouldn't be above 5v, I'm going to pull the driver board and look at what I see even though I have no idea what I'm looking for. Btw, this was what Clive told me was done to the driver board: WPC-95 Power Driver board (SN 53341103598): Removed burning P600D rectifier diodes and installed 8x zero ohm resistors in General Ilumination circuit. Fuses removed and checked, -- 2x 4 amp (F107, F114) and 6.3 amp (F108) slow blow fuses due to incorrect ratings. Capacitors measured. Replaced leaky capacitors; -- 2x 100uf/50v/105c (C1, C40) and 2x 100uf.100v (C22, C23). Remaining filter capacitors measured and tested fine. ULN2803A IC(U3) and 18-pin socket replaced as standard due to high failure rate. J101, J103, J104, J105 and J106 headers upgraded to high temperature. Capacitors, fuse holders and various areas around board had solder reflowed to fix suspect solder joints. All transistors curve-trace. Board cleaned-up. Two-tier full functional testing

Thanks Chris. I haven't for two reasons. 1st, I wasn't sure it was needed since it was stable without both mod boards and 2nd, I have never put a new connector on where the wire loops back through. What about getting more than 5v's @ tp101?

No bronze color on connectors. I replaced the only slightly discolored one at j106. The thing with the readings is, it is solid at 5.07v stock or with only one ung board, doesn't matter which one so long as both aren't connected. With both, it isn't a rapid decline to the reset threshold, rather the voltage jumps all over the place swing widely from roughly 5.01 to a low of 4.77. Just doesn't make sense. Everything by the wiki checks out. So just to be clear, 5.07 is within specs because I most certainly get the at tp101 and game rom pin 32 and it's a steady 5.07v with no fluctuation? I'm guessing I may have to buy a rotten dog which sucks considering I just had the board serviced.

I would like to do that.

Sent you a pm Chris.

Thanks. Definitely look into it. I'm open for anything at this point.

So I was fidgeting with it some more and maybe stumbled on something, maybe not. I unplugged the a/v board power and plugged it in and it resets immediately every time I do it. Is it a function of me doing it while the game is on or could this be my culprit. I seem to remember reading that if it bongs on a reset that means the a board reset to. Is this something or am I chasing my tail.

I figured as much Chris. To be clear, I didn't play 10 games or hours on end with it in. I did play what amounted to a full game by hand manaully hitting switches, activating modes, hitting both flippers at the same time, trying to induce a reset for approximately 10 minutes with no resets. Took the daughter board out and it reset and couldn't complete a game by hand. So when you say "regular path" that its on the driver board itself? I did try testing the 5v using various screws holding the ground metal backbox board to be sure the driver board was grounded properly and I got the same readings regardless. I suppose I should has just done a continuity test.

So after pulling the board and inspecting the backside, I could only find one thing that didn't look factory. It's a small metal jumper from the blueish cap leg next to the voltage regulator. Just below j138/139 in the first picture. I'm not sure if it's anything but I figured it would post a picture here in the event it was. Let me know if it shows up in the picture. image.jpgimage.jpgimage.jpg

Thanks zaza. Your sketches are always great and perfect for laymen. Thank you. Looking at your diagram, you are correct, I think I named the wrong cap, I think you are correct. So, does this qualify as a 5v hack and if so could this be my resetting problem?

Thanks for the explanation. So no chance it could be the cause of 5v my resetting issue detailed here?

So a small victory. Pinsider Jints56 graciously lent me a spare driver board he had serviced. Put it in the game with both bill ung boards plugged in and no resetting after 20 minutes of game play and another 10 minutes in attract mode. In the video the 5v stays steady at 5.09v. Nothing like the wild swings I was getting.

So it seams my board that was just serviced is faulty and has been shipped off for a second look. Thanks again jints.