I had a problem with the coffin ramp after fitting a cliffy; after reinstalling the arm connected to the solenoid would brush the metal ball rail just enough to stop the ramp going down, I could manually push it down with the slightest of pressure not sure if you have the same problem or not. To resolve it I just backed off the hex screws and moved it only a couple of mm, re-tighten and it was fixed.I did before but didn't find anything.
I do suspect the ramp coil for the coffin as it was making what I can only call a 'jamming' noise when trying to release the ramp.
I can successfully manipulate the mech manually so its not a physical issue that I can see.
I'm going to check the resistance but finding the part is a royal pain.
SM1-28-900-DC
In on way I want it to be the problem. In the other I don't if you know what I mean... I'll update shortly.