A quick Google search shows lots of hits and some seem to make sense to me. One that seemed okay with an RV is overspeed by revving too high when going downhill, possibly in mountain driving? Gear down too much to slow but then when wanting to go faster in the straight, not letting it upshift while revving the engine too much?
But most of us are not equipted to know what to do, so I go for letting the trained people handle this one if you are not up to resetting the code.
2015 Winnebago Vista 31KE on 2014 chassis