Power button unresponsive in hot weather

Yeah I've been putting the key in the slot just to make sure it wasn't a problem with the key.

 

I pulled the glove box out to check out some of the wiring in the dash and I saw this broken brown wire. What is this for? The photo was taken in the glove box area looking at the driver side. It's near the key fob slot.

I also found a little mouse house and some droppings in the tray under the blower motor so I'm preparing myself for some rat damage.