Anyone had this to happen to them? I think mine did!

Pat

How is it shorted? or what is it doing wrong?

All I can tell you is this. I had (by mistake) turned on the switch. The module got very hot and the wiring was damaged. The battery was ruined. I dont think it should have sat there and done that just by being turned on. How long? I'm not really sure.
Am I wrong? Maybe, probably! Who has the right answer?

Pat

What's happened or not to someone else in this case does not matter. Take pictures, provide a complete and accurate description of what you were doing and what happened and get in touch with Horizon. They're pretty good at determining what the problem actually is and taking the correct action.