You are having a overheating problem. You failed to mention a description of the car. If it has an electric cooling fan then you need to be sure it is working.
No. When the engine is running coolant is heated and expands. Excess coolant then flows from the radiator to the expansion (overflow) tank. When the engine is shut down coolant cools and contracts drawing fluid back out of the tank to keep the radiator topped off.
the light is triggered by a switch inside the overflow bottle, If the coolant level is low when the engine is cold, it will trigger the switch to turn on the light until the cooant warms up and expands. The hot water expands and flows through the radiator cap and into the overflow bottle and shuts the light off. Then once the engine is shut off and cools down, the coolant will flow back into the engine again and empty the overflow bottle. so if the light is on, you need to fill the overflow bottle to the "cold" mark.
The term "boiling", I am assuming, is referring to the coolant bubbling out of the radiator or overflow. This indicates that your engine is overheating, and should be shut off IMMEDIATELY. It is possible that er-repairable damage has already been done to an engine that has boiled over.
It has a tube between itself and the radiator. As coolant heats up, it expands. The expanding coolant goes through the tube into the overflow tank. Later, when the vehicle is shut off and the radiator cools, the overflow is pulled back into the radiator. The system is "closed", hence the coolant does not just "dribble away" when it expands like it did in vehicles many years ago.
Consider replacing your radiator cap . .
to dissipate the residual heat in the radiator it will shut off automatically
Could be a leak in a radiator hose, or radiator. ==Answer 2, Another Possibility== It could also be the radiator cap pressure relief valve action which vents coolant and/or coolant vapor to the coolant overflow reservoir/tank when steam is created in the coolant passages in the engine block. When the engine is shut off, the residual heat in the block can cause the additional pressure and/or steam.j3h.
you need to get the engine checked
carries water from and to the engine to the radiator for cooling, there are 2 and contain hot water when the engine is running and will still be hot and pressurerised for an hour after the motor is shut off.
In a closed cooling system, as the radiator fluid cools after shutting off the engine, the fluid contracts creating a vacuum in the colling system. This vacuum sucks fluid from the overflow tank via the radiator cap so as to keep the radiator full even when the engine is off. If the radiator cap's internal check valve is plugged or stuck shut, or the overflow hose/tube is clogged or not functioning, the vaccum will collapse the upper radiator hose instead of sucking fluid from the overflow tank as it should. Try to clean radiator cap by pushing on spring while submerged in clean warm soapy water so as to clean it out and also clean out overflow tank and hose/tube to make sure all gunk is removed. Also, make sure radiator fluid is clean. Better yet, drain and fill with new fluid. Should be done often anyway to prevent head gasket failure and or water pump failure. If no improvement, replace radiator cap with oem one from dealer. Do not use aftermarket. May not have check valve or may have improper pressure rating, leading to leaks and/or overheating.
The fan is ran by the computer. It will continue to run for a short time after the engine is shut off and is normal. If it doesn't shut off, that is NOT normal.