A little while back i parked on a tight street and popped my drivers door mirror back so nobody would give it a whack going by- when i came back out to the car i pushed it back out again but it kind of spring back quite quickly and it seems something is now loose or disconnected as the mirror glass although still attached isn't moving with the electric mirror control (which i can hear working)- how do i get in at the back of the mirror glass to sort this?? Can anyone point me in the right direction?