The electrical problem ended up not being an issue, just bad diagnosing by the former owner.Paul - welcome to the best IH Cub Cadet Forum on the internet. Your 1650 is a favorite and top of the line unit in the "Quiet Line" (QL) series.
Sorry to hear you have a brake and electrical problem. Not knowing how familiar you are with these machines, I'm wondering if your brake problem is really a hydrostatic control problem. We'll certainly need more details of what's occurring in order to help you out.
If it is a brake problem then adjusting them is fairly simple and described in the Service Manual. You can find the manual by going back to the Main Forum page, select the thread for IH Cub Cadet Tractor Forum, then select the 3rd thread on the list titled CC Manuals, then the link to the CC Manuals. This will take you to a page with a list of manuals for various models. You need to select "1x8-9 & QL Service Manual". (I wish the title said Quiet Line instead of QL since most new members won't know what QL means, and for that matter most new members won't know their model is part of the Quiet Line series until we inform them).
If you don't have a brake problem, but actually a problem with the hydrostatic drive, well then we'll need more info to help you out.
Thank you and everyone else on this site for all your help and advice, What a great group. Now to put this new knowledge to work.Paul - sounds like you have the external disc brakes. You can remove the rear wheels to have a look at the pads if you like but I'd probably just grab the Service Manual and go thru the brake adjustment procedure on page 2-72. If you can get good braking action following this procedure then your pads are probably "good enough". I think you'll discover over time that most of the braking action with a hydrostatic tractor actually comes from the hydro drive (assuming the linkage is adjusted correctly and the trunion isn't all worn).