My coach is only a year newer, and has a lot in common with yours, Dean. On my electrical bay legend, circuit breaker CB10 is for the seats. It is on the always-hot buss immediately above the left side of the solenoid, and the 4th one up from the bottom (#10 down from the top). You should have voltage on both sides of that breaker if it's fine. Check for loose nuts there also. This all presumes yours is the same layout as mine though, and even on mine there is one breaker that was switched to an open one at the factory so that made for two positions incorrectly printed on my legend.
That aside, Mike is correct - been there, done that from rotating the seats 180 degrees. The leads under the seat can get caught and connectors strained. I believe if one seat connector separates it can break the circuit to the other, as they are wired in series rather than off a common main, but don't quote me. It's easy enough to check under each seat for a separated connector, but on mine it was not a separated one but rather a strained one that had been tweaked enough it no longer would grab its partner solidly; it looked relatively fine until wiggling the right one allowed intermittent seat operation. There are multiple wires due to several seat control operations.
-Joel