Back cover small contact broken

I removed the back cover case of a Dell venue 7 to check the battery. After remove the back cover I noted there are two pair of tiny metal contacts on it, one located at left and top corner (considering "top" the smaller side where the power button is) and another locate at middle right. This contact are aligned with other metal contacts located at the mother board. As a first guest, I could say these contact are some kind of back cover removal detection(?). One of this metal contacs is broken, so I would like to now what's the function of this contacts. By the way the battery was good (the problem was in the charger, which we should test first) and the tablet turned on with apparently no problem with the back cover removed.