As it getting cold now i need to sort the front screen out on my other halfs saff, the switch is new(the little orange light does NOT come on when pressed

) the heated mirrors work ok when you push the switch but the front screen dont work atall ,and its a new screen???? So where do i look 1st to try and sort this out??? Any help anyone ???????
Oh the old screen did not work either

I know this is in the wrong section but not many people looks in the tech info!!