What's the detail on the problem??

Did you see this thread?

https://pinside.com/pinball/forum/topic/tech-tom-trap-door-wont-stay-up

faz

The other thread dealt with a trap door that didn't open fully.

If yours opens fully, yet doesn't hold it could be:
1. The hold portion of the coil could be shorted, or hold wire broken off the coil lugs.
2. The adjustment at the bottom of the bracket needs adjustment.
3. Possibly bad driver transistor, since it has to provide power to the coil for it to hold.

I would double check the coil stop and sleeve, while your down there. I doubt it has much to do with the hold issue, but worth check out, especially if you are going to be ordering parts.

Could you post a photo of the assembly? My TOM is at my parent's house, and I was working from memory. I was thinking it had an adjustable stop at the bottom, but I could be thinking about another bracket.

This coil has two parts. The high voltage part kicks the trap door up, and the low power part, holds it open. It works the same as a flipper coil. That's why you can hold a flipper up for a long time. Assuming the EOS switch is functioning properly, the coil doesn't melt or blow a fuse.

If it opens fully but doesn't hold, switching to a more powerful coil isn't the solution unless the coil itself is bad.

I just had a thought, is the spring missing? There should be a spring on the bottom of the assembly, above the rubber grommet.

Yes, but as you can see, stating the problem rather than your solution will give you a whole slew of options. This is a great community with a ton of experience.

Good luck!
faz

OK no, there is no adjustable stop.

If this is your assembly, the coil does look little strange. Look at the gap difference between the top and bottom of the coil bracket. Not sure this is a problem, but it looks odd. Do you have the manual that you can look up a diagram of that entire assembly? I would make sure it's put together correctly for sure.

J107-2 provides the hold power to the trap door solenoid. I would make sure that you have good continuity between J107-2 and the lug that brown/blue wire is attached to. The drive transistor looks to be Q48. You could always test that as well.