This one should be interesting, wonder why it burned like that. Apparently over fused, must have shorted out the 5 volts? This from a Meteor game, maybe the meteor hit the board, lol.
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Not my game or board, just repairing for someone. That connector is power, pin 1 & 2 is ground, 3 & 4 5 volts and pin 6 is 43 volts. I am guessing someone got the connector on wrong and shorted 5 volts to 43 volts. If the chips are okay it won’t take much to get it going.

I’m going to test the chips later and see. I got my numbers backwards before. Pins 19 & 18 is ground, Pins 17 & 16 are 5 volts and pin 15 is 43 volts with pin 14 being the key. If the key plug was not in the connector it would be very easy to get the connector off 1 pin putting 43 volts and 5 volts together which would then put 5 volts to ground and you have a big mess and being over fused does not help. Considering this connector is in the hardest place to see in the back box I can see how it could happen.

This is why you should ALWAYS check fuse values before powering up and when putting connectors on look at them first to make sure there is a key plug there, if not stick a tooth pick in it or something. Whoever did this is lucky the head did not catch on fire.

Dug out all the carbon and have my epoxy patch setting up. Tested the PIAs and memory chips, 1 PIA bad all the rest good so that is a good sign. Can’t get all the soot off the brown caps so I might just replace those, the rest cleaned up pretty good considering what it looked like before. Corrosion cleaned up, it was just starting to get to the components so some of those will need to be replaced but I am going to get it working before finishing that up.

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Took a little scrubbing to get most of the soot off. Removed burned part of the board and filled with epoxy. Replaced sooted up caps so I could clean under them. U10 was bad and a bad U6 socket. Jumpered for 2732s and installed those. Installed NVRAM. Board boots and diagnostics work. Displays, switches and solenoids all work. Only thing left to test is to hook up the sound card to it and check that out. Not the prettiest board around but considering what it looked like before it turned out pretty good.

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Sound works. I’m done with this one, glad it could be saved. I’ll post a picture of the back once I get it unhooked after letting it burn in for a few hours. I had maybe 5 hours of actual work on it and around $30 in parts including the NVRAM so it was worth the effort.

Here is the back of the board.

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