Checked fuses 1 and 8. Good. I can raise the seat back manually, but it flops right back to full recline position and the switches do nothing. I'm trying to get the control box out, but it feels like it's being held by approximately 6mm 12 point bolts. I don't have small wrenches in anything but 6 points. I can't take the seat out because it is centered over all of the mounting bolts.

 

John,
It sounds like one or more of the connectors have come loose underneath. That is a problem.
You need to be able to remove the seat to fix this problem.
Looking at the mechanism, I wonder if you can reach the shaft highlighted at the front base and turn it manually? See pic.
You may have to remove the other seat to inspect the forward/backward movement mechanism and learn how to fix this....

 

Swapped controllers and found that the controller was the problem. Disassembled the controller, cleaned it up, soldered in jumper wires, got it partially working, found other gaps in circuit board lines.
Ordered a used controller and am continuing repair on my bad one to keep as spare.

 

Crikey John, that's excellent. Well done !

 

Agreed, well done....

 

Well done.

Bet you have a sore back crawling under the seats to get the seat modules out. The cabin height is limited in the X100 so you can see how someone lowering the seat can crush the seat modules.