If you have a frozen car radiator, there are a few things you can do to thaw it. The first is to place the radiator in a warm place, like a oven or stove. The second is to use a hairdryer on high heat to heat up the radiator. The third is to put ice on the radiator and let it sit for an hour or two. Finally, the fourth is to put the radiator back in the car and drive it around until it warms up again.