Hi John, Thanks for sharing your question with us, and welcome to the Automatic community! At this time, we do not support RV's, as there are many technical specifications and questions that must be addressed/answered first. We may add support in the future, but at this time it is not part of our product roadmap.
Unfortunately, it's still an unsupported vehicle. While it may have worked in the past, we can't provide troubleshooting assistance since it is not supported. We don't recommend using the adapter on your vehicle, and if you decide to use it anyway it's at your own risk. I really wish I had better news!