Alright guys, So needing some guidance. Williams Fire! did a flipper rebuild, basic top side teardown and shop. Added a cointaker LED kit and now the game is having issues. Here are the symptoms:

-Game boots fine but randomly mid game it will just reset. Not always but id say every third game, but sometimes any game
-Reset once and gave the "MemProt Failure" message
-Sometimes it seems like the multiball sequence gets messed up and it decides to dropped locked balls when it feels like it.
-Game only did this once, but it seemed to lock up and the left lower sling shot kicked on and stayed on. I immediately powered off the game.
-Game has memory and maintains the freeplay setting when powered off

Recent things I have done to try to correct/troubleshoot the issue:
-When I brought the game home I found corrosion on the battery holder and replaced it with a remote mount. I can measure 4.5 volts at the board on terminals using B1+ and B3-
- Removed MPU board and reflowed all pins for the molex connectors.
- Checked power from the power board TP1=+4.97, TP3=+12.42 TP4=-14.54
- Ran CPU test with coin door open = LED indicator at U46 shows what looks like a zero,but half of it flashes in and out like a 7 almost??? When you first press the test button the U46 display briefly lights dimmly for a split second then the game seems to boot right up and do the 0/7 thing.
-Coil test runs fine with no issues or resets
-Switch test looks good with no unexpected closes on switches
-Coil door memory switch tests good

I am wondering if I am dropping power during play from the power supply causing a reset??? I am going to pull it out next and check for cold solder joints. Was thinking a cap kit, but the board looks like it has seen better days and thought of going to an Xpin replacement board. Think i'm chasing the right direction or possibly something else? Any suggestions or help would be appreciated.

Hopefully this helps. I included a close up of the power board where it looks like it's gotten really hot. I unplugged the ribbon cable from the MPU board for a cleaner picture. Thanks for the help!

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Sounds good! The U25 Ram is still soldered into the board. That's the reason I didn't go the NVRAM route in the first place. I don't mint soldering in components, but chips scare the crap outta me. I will get a new capacitor kit coming I think and just do them all throughout the game.

Thanks a ton for the links!!! This is probably my 5th or 6th system 11 that I've gone through and I was not aware of the issue with the B/Rs. I really appreciate it!! I was thinking the PS was dropping voltage during game play causing the reset. It sounds like you guys are thinking the same thing and the Caps would be the easiest culpret to take care of first anyways. Really just general maintenance on these old games and keeping it simple is always the way to start. I just wanted to make sure I wasn't having some signs of RAM failure or anything more serious.

Now what are your thoughts on just buying a new Xpin PS board Vs rebuilding the williams powersupply??? in the past espically on the arcade side of things I have had a pretty mixed bag when rebuilding old power supplies. Seems almost better to just get the newer board with better modern designs. What are your thoughts?

ebay.com link: itm

Thanks a ton for the reply! I am currently watching the video where he is repairing an mpu for pinot. Hopefully this will give me some guidance. Since reflowing the connectors on the mpu board it hasn't been acting strange with odd ball lock behaviors, but it is definitely randomly ending the game still.

Well I live in the pinball wasteland known as Wyoming so out here I am about as good as it gets for board repair or pinball repair in general. There is only a few of us pinheads in the region even. I have used Clive over at The coin op Cauldron for board repairs in the past and have had great luck. The more I see everyone's comments it may be worth just sending out the whole board set to get looked at and gone through by a pro. I really enjoy game repair and learning more all the time, but board repair seems to be an art form when done correctly. I will see if I can repair the female end of that connect and probably just buy a new PS board.

I will look at those tonight. Thanks so much to all of you for your tips and expertise. Without people like you guys willing to share your knowledge this hobby would die out.