Well if it were me I would go back to the dealer and have them look at it plus document the issue for later. Remember if you took it in before your warranty expires then it's a known issue and thus will be covered under the warranty.

Good luck!

 

If you go on Wikipedia and do a search on throttle by wire there is a interesting low down on on the feed back checks that this system does. Probably numerous places this system could error and any one will cause it to fail safe unless there is a Semi behind you. What surprises me is Harley cleaned the TCA. If that is the problem he should have replaced it along with that part of the wire harness. This part is pretty much on cars now(its on my 05 with 55K and not a problem). Pretty much all will have it. It controls better when you shut down the throttle. You can see it in my tack on my car as I drop the throttle complete off it will bounce the tack slight as it adds air but no fuel to the engine. With a cable driven butterfly it was difficult to do that. If it was my bike I would get me a good service manual along with the electrical diagnostic manual and study just how it all worked. Take my best guess as to the offending part and replace it along with any harness hooked to it. I have been on here a short while and have seen two of these for sure. However bet this is rare (for number of bikes out there) You have a defective part. Bet one good pressure washing of an 09 would destroy the electrical system and you read about people doing this all the time on the Forum.

 

The service manager at the dealer where I bought my UC said that what he sees is connectors on the ECM under the seat getting bumped just enough to cause the error code and put it in limp mode. Don't know the location of the ECM on your bike, but his suggestion was to pull the big connector from the ECM, clean it and put dielectric grease on it, then plug it back in as tightly as possible. If your ECM is under the seat and the failure occurred following a bump in the road that caused a bounce, that might be something to look at. Glad you weren't hurt and I hope you get to the bottom of it.