When the seat heaters are working... you'll know! They get very warm to the touch. As I said in a previous thread, my passenger side is working perfectly, when I turn on the passenger side and put my hand on it 2 or 3 minutes later, it's very warm. The bottom and back both heat up. Never did get my drivers side fixed... took to two different interior guys and both could not fix? Chrysler wants $600.00 so I just deal with a cold drivers seat.