Could be a stuck open thermostat.
when the car starts to over heat
Possibly over heating and worst case scenario a blown engine.
Stand in front of the car facing your back to it and then bend over...the cooling fan will plug in itself.
So that a car will not over-heat and blow up
without it the car could over heat and catch fire
Brakes don't contribute in any way to cooling the car
If there is no cooling system, the engin will overheat.
While your car is running the engine is heating up. While your driving you have air being forced over the radiator cooling it off. When you are sitting still you don't have that air so your engine is heating up even more so the cooling fan comes on to help cool you engine off. Via cooling the radiator.
It is heated to such a high temperature by going over the engine which is really hot and is part of the cooling system, the cold air goes over some part of the engine and comes out hot. It is part of the cooling system of a car, so therefor if your car has overheating problems turn the heater on.
Any particular kind of car and motor?
BAd thermostat. clogged radiator, cooling fans not working, blown head gasket.
NO it will not, It has NOTHING to do with the cooling system whatsoever.