to the forum!
Mike, I wish that I could help you, but I don't have the paperwork with me that tells how to work the awning manually. Other forum members may be able to tell you.
I don't have the Tracer 3150, but on my LaCrosse 303 There is a access panel about 1' square located under the trailer, curb side. I believe this is where the slide motor is located and where you would manually open and close the slide.
Forum member RV Guy is PT management and he's on this forum on a regular basis. I'm sure he can help you better than I can. You may also contact Prime Time with any question using their contact page on ther web site. They are excellent at getting back to you very quickly.
Here's the link; Prime Time Manufacturing, Manufacturers of travel trailers and fifth wheels
I hope this helps.
Good luck and happy camping.