[Tom Line]

The only time that you need to worry about a jumper on the digital side car (and someone can correct me here if I'm wrong), is when you are plugging in a servo.

What you did with the jumper was to jump power straight to ground - you short circuited the entire board. You are lucky it has built in protection or you would have fried it.

Please try to read through the various controls manuals provided by First if you haven't already. They provide a great starting point for someone new at this. Also, try to use punctuation and capitalization. It's hard enough to read through the hundreds of posts - don't make it any harder!