I got lucky that just the speaker failed open, on my meter. I didn't have a 8 ohm handy so I installed two 4ohm in series from MTH upgrade kits. I know, a little ugly with the hot melt .
I just added speaker baffles after the video to reduce the tender from rattling, but it still rattles.
I hear the smoke unit turn on with aux 9 and off with aux 8 (I think?). I don't see any form of cherry switch although the chuffing times fair with the drivers. The smoke unit chuffs too? Must be back EMF??