No, the 12VDC is created on the board and heads right out to some connectors, it is not attached in any way to the flipper dpdt relay or flipper return (ground)....I think you are misreading the schematics. Follow the red line.

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Status indicator LED for presence of 12VDC power. That is not a direct short 12VDC to ground return.

Your original problem is Rudys eye movements? (not a flipper problem?...the relay there on the page is only for enabling the flippers - nothing else)

Check the solenoid table. Start check by briefly grounding the appropriate transistor tab to see if his eyes move (Q26 and Q20) If they work there, then there is upstream problem (transistors/logic) If it does not work then downstream problem/wiring/supply voltage at the eye solenoids, something along those lines.

Then I have 2 questions:
Where exactly are you measuring 12V on the 50VDC circuit? (there'd be more wrong than just the eyes, all the 50VDC coils wouldn't work - so what's going on with the rest of the game coils?
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What are you measuring on the eye coils directly?

If this measures 12VDC, none of your high voltage coils are going to work. 50VDC is supplied by bridge BR3. Check AC input to this bridge.

I'm asking what the 50V circuit measures with everything plugged in as it should be...and if all the other high voltage coils work. I think what I am hearing in the text is a bunch of plugging and unplugging connectors without a defined troubleshooting path. Is this just a problem with the left/right eye solenoids, or do we have other coils not working? Run the solenoid tests.

Keep in mind the most likely two causes of the eyes not working :
A) broken power side supply wire to those coils,
or B) not getting grounded on the trigger side.

And, also keep in mind that the other eye directions "open" and "closed" also use the same coil power supply as well, so if those eye directions work there is not a problem with power supply for those solenoids.

We don't need to be fooling around with the measuring the main solenoid power section of the driver board, unless we have a systemic problem with a bunch of the coils.

Weird. If you don't run across something quickly, here's where I would start.

Disconnect all cable headers from the driver board, check continuity between TP1 and TP6. If you have a short, it is isolated to the driver board and go from there.

If no short between test points, the problem is off the board. Go to the removed plugs and start testing there. Since they are all disconnected and specific wire harnesses are going to different places, the goal here is to determine if the short is on the playfield, or somewhere else like the cab. Could be a problem with the coin door interface for example.

You'll need sharp probes or a wire lead to get into the female pins of the connectors. Put one meter probe on J116, J117, J118 pin 2 (pin 2 is +12VDC for all these connectors) with the other probe the other pins on the respective plugs J106,J107, J108. Nearly all the pins carry the +50VDC on those 3 plugs. I would test playfield connector to playfield connector, backbox to backbox, cab to cab -- looking for one with continuity which would indicate which wire is shorted. From there you'll know what colors of wire to focus on tracking down.
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