Welcome to the Forums and the world of Vintage Argosy ownershp.
Originally Posted by Wingrider72
Already lined up shop to install a new set of tires and check/repack bearings for the long ride home. Not familiar with braking system on Argosy, brother in law said brakes didn't work with his controller, so assuming I'm gonna have some work to do. Wondering if anyone can give me the basic rundown on what kind of braking system this trailer has and how to check its condition.
What you are describing is the usual symptom of a Vintage Airstream product that hasn't had its 7-pole Bargman connector re-wired to the modern standard. Airstream didn't adopt the industry standard for wiring the Bargman conector until some time in the late 1980s or early 1990s. The color/function of the wires and their positions as delivered from the factory can be found in this link
. Your Argosy would originally have been wired according to the diagram on page 2 of the link above. The current industry standard wiring diagram can be found at this link
Your Argosy will have the typical industry standard electric drum brakes. The brakes are likely either Kelsey Hayes or Dexter 12" x 2". If parts replacements become necessary, it is quite likely that it will be less expensive to purchase fully loaded backing plates that have all new wear parts and can be found at most any trailer repair facility.
Good luck with your project!