Ok so we got a cold front that came in last night on thanksgiving and my factory battery crapped out. I removed it and went and had it tested and they said it was bad so I bought a new bigger and better one for my jeep which is an 05' TJ, I'm home now to install it and noticed at the bottom of the plate were the battery sits there's this little circular disc that sits on a spring and when you push it down you can see a metal disc under it and there's a wiring harness attached to it that runs under the plate! Can anyone tell me what this is before I put my battery in because the new one I got is for my jeep but it doesn't look like when I put it in it's not gonna push that disc down! Or is it like a safety switch and it's not suppose to push it down? Need help please because I'm working on it now I need my jeep back! Lol thanks in advance.