Hey all,

I just picked up a Shadow the other day with a problem and I've started diving into the issue, and I was looking for a bit of help. Basically, when I turn on the game, everything will light up and the game will boot, but after maybe a minute or so at most, the DMD will start to garble and the game will shut down. I haven't tried to start a game, but I was able to enter the test menu before things shut down. There is no sound at any point and I just hear some light crackling in the speakers. If I turn the game off and on, nothing will light and I only hear the light crackling. It has to sit for some time before it will actually "start up" again.

Looking at the CPU board, D19 and D21 light on startup, then D19 goes out and D20 begins to blink rapidly. At shutdown, D20 shuts off and D19 lights back up, with D21 staying lit throughout. If I turn the game on and off after that, D19 and D21 stay solidly lit; D20 does nothing.

I've been trying to work my way through pinwiki and was hoping for a nudge in the right direction. I removed all cables connected to the CPU board except for J210 and get the same behavior as above. I did take out the batteries and replaced them, and didn't see any obvious signs of corrosion, but I didn't pull off the battery PCB to look under it. Overall, the CPU board looks newer than some of the other boards in the backbox. I've attached some pictures for reference and thanks in advance for the help!

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Absolutely Lloyd, and it's a pretty long list I also wasn't sure if this was definitely a reset issue since the game doesn't come right back up after it shuts down. Plus, I came across a Pinside thread from a year ago that sounds like a similar issue to mine, but I didn't see the final fix posted:

https://pinside.com/pinball/forum/topic/wpc-s-resets-but-doesnt-turn-back-on

Thanks Chris. I don't have a PLCC removal tool, and I'll see if I can grab one close by. I did pull the board and tried to reseat the chip in place, same issue when I hooked things back up.

Since I've got everything unplugged from the board except for J210, does that mean there is a problem somewhere on the CPU board or the power interface and transformer? Could another bad board in the system still cause an issue? Should I pull the power from them?

In the end, I'm completely fine with sending a board (or boards) out for repair, and I was hoping to figure out if it is a board issue and which ones to send out.

Not sure what the exact time is required between boot ups, and waiting 15 minutes is too short.

Thanks Pin_Guy, especially for the great picture. I checked the board at a couple of the places listed in the older Pinside thread I linked above (including C31) and got 4.99V everywhere. I also tried taking the MPU board out of TS and connecting it to just J210 of WCS (leaving the coindoor open) and the CPU did not boot (i.e. D19 and D21 stayed lit while D20 did not light).

Chris, just to make sure I understand you correctly, are you saying take the MPU board from WCS and put it in TS after swapping the ROM and security chips? I did try reseating the ROM and security chip in TS MPU board, no help.

One thing I did notice when I popped my TS board into WCS, I still got the "bong" sound at startup from WCS, even though the CPU didn't boot. Think there is an issue with the sound board too?

Hah, you're making me doubt myself. I was listening for it though since I never heard the bong when I would get TS to boot up after letting it sit for awhile.

Took a look at the sound board and J4 wasn't seated properly, so now I get the single "bong" at bootup and no static.

I'm taking the boards to Allan Davidson tomorrow. I'll definitely report back to close the loop on this one. Thanks for all the help everyone.

I took the boards to Allan this morning and even though the MPU board had pretty much been isolated as the problem, he checked them all out just in case. Long story short, they were all fine and in the end, it turns out the microprocessor (68B09E, part no. 5400-10320-00, chip at U4 in the manual) had gone bad. The chip is socketed, and Allan had some spares, so it was a very quick fix once he diagnosed it. He also got the batteries off the board and installed some NVRAM I brought along while I was there (I brought my WCS MPU board to get some NVRAM too).

I got everything put back together tonight and the machine is running smooth so far. Thank you all very much for your help in this thread, and definitely a big thank you to Allan, who luckily is just a short drive away for me. Not only did he fix me up, but he, like many other pinball folks I've come across, was just super nice and had no problem at all answering all the dumb questions I was asking. Thanks again everyone!