Pinball Basement board?

Try reseating J101 and J114 power connectors on the big power driver board, and J210 on the CPU board. Any burning/discoloration on the J101 connector housing?

Time to see pictures of the thr boards with the game on.

Since all the LEDs are lit that supposed to be, that tells me there are no blown fuses. Just because the LEDs are lit, doesn't mean these are all good voltages.

The 5 volts is very important to measure as to know if the game is not booting up because the voltage is too low. Set your meter to the 20VDC setting and wedge your black lead under the ground braid wire at the bottom of the backbox. Turn the game on. Then you have one free hand to measure the 5volt test point on the driver board at TP2 and then also measure at C31 + side marked by the arrow. Normally, should only see a slight 0.03V difference between these 2 points. Can you post what you see on both measurements? I hope you see at least 4.94v at C31. pasted_image (resized).png

So when you say D20 on the CPU board is blinking, is it blinking about every half a second?

Is this only after it has been on a while? Is that when it goes into attract mode? These symptoms usually are a sign of a low 5 volts.

So I am afraid that I do see some battery alkaline (not acid) damage on the CPU board. Even though there is damage here, this very likely would not cause the game to boot as it is not a severe case of damage. At worse from what I see here is that you would have some switches not working. But the board still will need to be repaired properly.

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Is the new CPU board from Pinball Basement? If so, I'm afraid I would not put that in at this time as their quality has not been great so far. I hate to put that into the mix right now.

It is best to get the game booting and playing before deciding what to do with this original CPU board.

So the first part sounds like the MPU booted up.

Try these things..
Measure the 5 volts on the Driver and CPU boards, as previously mentioned
With the game off, press on all the IC socketed parts on the CPU board and reseat all the ribbon cables at all the connections.
Try the game again.

I just missed posting my previous statement before seeing your 5 colt measurement.

Wow. That is too low. Can you retest them again after reseating J101?

If it is still low, I believe BR2 bridge rectifier needs to be changed on the driver board.

Just easier to remove J114 on.the left side of the driver board and retest TP2. If any board is loading down 5volts, that will tell you.

Have another driver board you can test in the game? At least you will be able to test the rest of the game.

Time to gave the board repaired. Anyone you know works on boards and can change BR2, C2, C7 and the other capacitor above F101 to F105?

Yeah, I would definitely hold out on.the CPU board swap until the game boots with a good 5volts. That way you can tell there was a problem with any of the parts you may had transferred over to the new CPU board.

Makes things easier to identify an issue taking small steps.