The 1953 Lincoln was the first car that had a rear window defroster. It also was the first car to have an optional 4 way power seat.
It is probably the sound of the defroster fan.
windshieldwheelwater pumpwindowwindow defroster
If you have the defroster in the on position the ac will do that.
It heats the windshield to melt the ice.
Because it's not a defroster button! It's just the symbol for ventilating the air into the car. It shoudln't be called a defroster since defrosting is meant by heating up the coils that you see at the back of the car. I'm pretty no car has wires in the front!
First you start the car. Then you let it idle or drive it until it reaches operating temp. Finally you turn the heater on to the defrost setting.
Defrost the windshields so you can see where you are going. Useful in icy climates.
dry air removes moisture better
You have a leaking heater core. You might smell antifreeze if you turn on the defroster.
If there is an oil leak inside the engine compartment of the vehicle. The defroster could have some of the smell go into the cabin of the car. The engine should be checked for any oil leaks.
There can be several reasons a rear defroster fails even when the light on the defroster switch indicates it is on. The most likely reason is that one of the metal defroster tabs along the side of the back window has separated from the defroster. If the defroster tabs check out as still attached to the defroster then you need to do a little checking with a volt meter. The first thing to check is the voltage directly on the tabs themselves. This should be around 12-14 volts. If the voltage is zero then there is very likely a broken wire someplace between the defroster relay and the defroster. If you have 12-14 volts a the defroster tabs then there is something going on with the grid which is normally broken defroster elements, those long thin horizontal lines on the back window.