Pass 42 Sorry I can't tell you where the buzzer is located, but on my Tradewinds my dash can be pulled forward a little bit so I can see inside. I just looked down there and found the buzzer that was making the noise and took it loose. It has been 3 years or more since I pulled it.
My dash is held in place by Velcro so it is easy to pull forward and have a look. Tcooper mentioned where one of the sensors is located. You might check that also. Hope that helps.
Sorry, I had not read far enough to see the solution. I may now check my coach as I believe I was having the same problem you were having.
Arnold