I have a TomTom 6100 GPS which I have mounted on windscreen. The unit gets very hot from sun and at times after parking car and on return the GPS is so hot you cannot handle it. I have tried to shield it from direct sun by inserting a tinfoil cardboard (foil facing outwards) but it doesn't stop the overheating.
I am worried that this kind of heat may damage unit and wonder if anyone has better suggestion for protecting the unit.