Went to repair my daughters Metro PCS LG K7 phone that she dropped. Upon opening the back, a small "T" shaped...

Check the inside cover of the unit. Its been years since I worked on these units, but if I remember correctly, Nintendo put in a small aluminum tamper tab at one point as they wanted to do all repairs and some units had these where when you opened the unit up, it would break cutting the circuit. You might have one of these units. Your going to need a really fine tip soldering iron to close the circuit if this is the case as its extremely easy to hit the other components next to it.