This was my first assumption but I overthink everything and it took me a half hour to get all the documents together to answer the "Why?" Conflicting connection information in the specific game manual never helps either.

If you read my post and understood it you now know more than most pinball owners ever wanted to know.

Interesting information along these same lines ... STTNG has no 4th flipper circuit connection but uses the Flipper 4 EOS switch circuit on the Fliptronics board for the spinner! How crazy is that?

Both are very good reasons and I would concur with option 1; without counting the EOS or direct ground switches STTNG has 69 switches.

Yes this should read "The tab of a TIP-36c is not connected in the same way externally."

This is very concerning as reversing the outside wires would forward bias both the primary and secondary flyback diodes all the time and your 50V is just just waiting for a path of destruction.

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Based on an assumption that WPC95 flipper control and WPC89 flipper control works the same way, as soon as the CPU activates the flipper coil, BOTH the Power and Hold transistors energize and would short your 50V right through both transistors to ground; this would allow a destructive amount of current to flow through these two components and may have causes some board damage. The destruction of the one coil diode shown in your picture is actually a good thing as it would have broke the short circuit by forcing the current to flow through the coil windings instead of around it.

You definitely want to either test and or replace both your drive your drive transistors, the best way to check this is as follows:

If the board is on your bench check for continuity between any ground point and on the board and to J120-4 and J120-6, continuity here would indicate a shorted transistor.

If the board is installed in the game you could perform the same test as above by removing J119 and J120 but you can use any ground point that's easy to access for checking between J120-4 and J120-6 to ground. If you do this check with the game powered on you should keep the coin door open or remove the 50V fuse as a precaution.

ChrisHibler Thank you for all your efforts in maintaining this page, it's a great resource for folks working on their pins and it provided with just the right amount of detail that most can understand it and also more detailed information for those of us that want this kind of information.