deskthority

Hi,
I've been working on a Model M for the past little while, and it's been giving me some troubles. I've fully bolt modded it and none of the keys are responding. The board was fully working before the mod and had no problems. I know for sure it's not the controller boards since I've tried multiple ones and none of them have worked. All bolts are properly tightened and I really see no reason for it to not be working. The only thing that works on the whole thing are the lock lights, and it makes a load of beeping noises when plugged in that fade off eventually.
Has anyone else had the same experience? Advice?
Thanks!

Might be obvious, but are you sure you put the membranes in the right order and orientation?

Pretty sure I ordered them correctly, but that must have been nearly a year ago. If all else fails I'll take it apart and see what's up.

Do you plug it in before you start the computer or afterwards?

Both. None of them made a difference sadly.

could it be a short in the tracks of one of the sheets?
or maybe you are screwing too tight and there is a permanently pressed key?