I recently installed a 10000 lb winch before that everything was working fine. This morning I got on my 08 jk to go to work when I realize that the battery was dead and no I did not leave the lights on. However when I got home from work I decided to go check out the problem I jumped the jk and started right up however now I have a red flashing light on my dash. And if I disconnect the neg. Batt. Terminal the jeep dies. I checked the winch it's installed correctly I even disconnected the winch same problem. Is it that my alternator is going bad or just the batt. Thanks

 

What year's the Jeep? Odds are it's the battery, or you somehow shaved insulation from the red wire creating a non-op ground.

Alternatively, if the winch is a generic brand it could have an internal ground that is sucking power from your battery (this could happen from any winch, it's just that Warn tests for it as part of the QC).

 

If its the stock battery that came with the JK then you didnt do a thing wrong. Your battery has reached it lifespan. The Jk's stock battery only last 3 years...I just replaced mine 2 weeks ago..