Yep, check/clean/tighten your winch's electrical connections at the battery (make sure both connections attach directly to the battery). Then if that doesn't fix it, one of the solenoid connections might be loose.
The brushes/armature for the motor may be rusted. I took mine apart a few years ago and was able to clean them and the armature up. Getting the brushes back together was tricky, but if I can do it anyone can.
Sounds like your friend has a Warn winch to repair...if he is a true friend.
I would not even think about returning an item I borrowed from a friend in worse condition than I got it. But, that's a whole other topic.
Warn is the best place to buy used parts. Their customer service is great.
Life with Christ can be explained like a Jeep...
Being in the Word... grows your tire size.
Prayer... gains more ground clearance.
Fellowship... Is like having a good spotter.
The more of these you have... the easier it is to get over obstacles in your path.
.[URL="http://www.jeepforum.com/forum/f194/dcope17s-thoughts-bible-please-read-only-do-not-post-1333441/#post13115090"]My Bible Thread[/URL]
I hear ya. I really can't hold him too responsible as I sold him the rig that had the winch on it. He was supposed to bring me the winch when he had a chance to take it off, as the winch was not part of the deal. As I had no need for the winch, I told him to take his time. Unfortunately, having it sit outside, unused for over a year, caused the issue. He offered to take a look at it, so eventually, it will, hopefully, be working again.