I tore into the seat heater to see if it was a simple fix. The seat back works fine and the seat was an open circuit. Both bolster heaters checked fine but the connections to the front section and BOTH seat connections were broken. The PO must have been a "Heavy Sitter"

I cut off the felt pads covering the connections, soldered in a couple inches of extra wire for a strain relief. Covered all the connections with heat shrink and hot glued the felt cover pads back on.
Ohmed good and everything heats up like new.
Total cost $0.00 , Priceless

The passenger seat is in the same condition, I'm going to see if the repair to the drivers seat holds up, then I'll tear into the passenger seat.