I have had my STTNG taken apart for the last few weeks so I could give it a full shop job and have the cabinet parts powder coated (coin door, legs, etc.).

Yesterday, I booted it up with the DMD hooked up for the first time since the process began. I'm getting a "slam tilt switch is stuck closed" error on the display and I can't do anything with the menu. All of the coin door hardware is sitting on the bottom of the cabinet still (no coin door yet). Both slam tilt switches are physically open. What should I look for?

Here's a little extra info in case any of it matters:

* I installed Herg's LED OCD and GI OCD boards. While running the wires for the GI OCD board, I disconnected J205, J206, J207, and J212 to run wires. The game was off when I did this and I'm fairly certain they are all back where they belong.
* The GI OCD board comes with a new ribbon cable that runs from the PCB board to the CPU board (then onto the GI OCD board). I'm certain all three connections along that ribbon cable are secure and properly seated.
* The assembly with the 4 coin door switches has a ground cable that is currently not connected to anything. I connected it to another ground lug once I saw the error and rebooted, but the issue remains. I'm not sure if that would factor into it at all, or if it needs to be connected to its own ground lug on the coin door?

Any help will be appreciated!

I can't get into the menu. No matter how much I angrily mash the coin door buttons, I can't get past the slam tilt error message

Could it be diode D1 in this schematic?

Screenshot_2016-04-14-22-54-43_(resized).png

There is some that had been mitigated and cleaned by the original owner. The game was working fine before I stripped it for cleaning.

I am fairly certain they're all seated properly, I checked them again after I saw the error. But I'll definitely make sure when I get back to it later today. After I check that, I'll remove the board and show the battery damage front and back.

Any other ideas on what could be going wrong, in case it ends up not being the MPU board?

You were 100% correct. J207 was off by one pin. Looks like when the board was repaired, the tech just snapped a connector to the right size. So it looked like it was seated properly, but wasn't. Still doesn't excuse me for missing it in the first place, but I gotta blame someone!

Thanks everyone!