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Basically, a radiator fan blows cooler air through the radiator to lower the coolant temperature and cool off the heat from the car engine. Obviously, when the engine is running, it produces heat. When the vehicle is moving at high enough speeds, the flow of air through the grille is enough to cool down the engine.
How do radiator fans turn on?
On most modern cars, the cooling fan is controlled by the Engine Control Unit (ECU) which gets a signal from the coolant temperature sensor. If it’s not working, the fan won’t turn on when it needs to, which means the engine might overheat.
When should a radiator fan turn on?
Temperature will often determine the time that a radiator fan starts up. A temperature-sensitive switch functions to turn the fan on and off periodically. Radiator fans are designed to start when the temperature of the engine coolant reaches around 200 degrees Fahrenheit.
Should radiator fan always on?
The engine temperature should trigger the fan to turn on. It will also turn the fan off once the engine has cooled to under 200 degrees. You may have heard of a part called the radiator fan switch or temperature fan switch. This is linked to a thermostat and works much like your home’s HVAC system.
Should radiator fan run when AC is on?
When the AC compressor is activated, it is actually expected that the radiator fan runs. For instance, the radiator fan is needed when the temperature sensor of the cooling fluid in the lower tank reaches approximately 212F.
Can I drive my car if the fan is not working?
As such, you should never drive your vehicle if the cooling fan isn’t working even though you can. If the radiator does not have cool air blowing on it constantly, it will overheat eventually, so you’d need the perfect combination of weather and traffic to drive effectively without a radiator fan.
What happens if radiator fan is not working?
What happens when a radiator fan stops working? It will cause a loud whirring noise and a stuck open thermostat (which will not allow the engine to reach the average operating temperature). A lousy radiator cooling fan could cause a blown circuit fuse, a malfunctioning relay, and engine overheating.
Why Does My car fan come on when I stop?
Engines operate at their most efficient when they’re hot but not too hot. The fan turns on when you’ve stopped driving because no more cooling air is flowing into the engine bay. This causes the temperature to rise, automatically triggering the fan.
Should radiator fan turn on when AC is off?
The AC controls may operate the fan from a place in the control circuit after the normal temp sensor so everything is OK when the AC is on. Also the Fan may be on continuously when the AC is operating.
Does the thermostat control the radiator fan?
The thermostat is an important tool that your car uses to be properly cooled. If this thermostat doesn’t open when the engine reaches the working temperature, the coolant will stay inside the engine block and the engine will start to overheat. This will result in the radiator fan not working.
Is it good to connect radiator fan directly?
If the fan is direct, the engine remains cool all the time and doesn’t achieve the desired temperature as advised by engineers / required by the engine, the fuel doesn’t burns properly resulting un-burnt fuel goes into the engine oil gradually resulting in weak engine head etc etc.
Why does my radiator fan only turn on with AC?
The most likely culprits are a thermostatic switch, fan resistor, temperature switch, low-speed or high-speed relay, or a wiring issue. When the vehicle has the AC on, the engine needs extra help cooling so the ECU commands the fan to be on any time the AC is on.
How long can you drive without a radiator fan?
No more than a mile or two. A bit more if it is cold outside, a bit less if it is 100F outside. Less with stop and go traffic, perhaps a bit more if you are at moderately high speeds, 40 to 45 mph, with no stops.
Can a broken radiator fan cause overheating?
Engine overheating: A bad radiator fan can cause the engine to overheat, especially at low speeds. If your car starts overheating, pull off the road as quickly as you safely can and turn off the engine. An overheated engine can quickly get ruined and lead to expensive repair bills.
How do I know if my radiator fan relay is bad?
Bad Cooling Fan Relay Symptoms The engine runs hot or overheats. The cooling fans don’t work. The cooling fans keep running. Warning lights. Poor air conditioning performance. Swapping Relays. Measuring the Relay Coil’s Resistance. Listening for Noises.
Why does my car sound like it’s running after I turn it off?
Air can enter the coolant system in other ways besides just from a leak. Coolant fluid changes are required as part of ongoing maintenance for all vehicles, and when these procedures aren’t properly executed they can cause air to leak into the coolant system, creating odd noises to occur once the car is turned off.
Why does my engine cooling fan keep running?
This is normal in many vehicles, such as BMW or Mercedes-Benz. The radiator fan may run up to five minutes and sometimes longer. Unless there is an electrical issue, it may stay on all the time until it drains the battery. Running cooling fans help cool down the engine even after you turn off the car.
Should fan be on auto or on?
Keeping your fan on AUTO is the most energy-efficient option. The fan only runs when the system is on and not continuously. There is better dehumidification in your home during the summer months. When your fan is set to AUTO, moisture from cold cooling coils can drip and be drained outside.
Can a car run on one fan?
Yes, of course. But, the engine might get a little hot, and it isn’t a good idea to continue to do so without getting the other fan (or two) repaired or replaced… If there is more than one fan, there is a reason for it.
How many radiator fans does a car have?
A lot of drivers’ vehicles will actually have two radiator fans. One, both or neither may be running at any given time depending on the conditions. When you are cruising at highway speeds, the air rushing over the radiator and around the engine will help control the heat.
What are 10 common causes of overheating?
Common reasons for overheating engines Too little or no coolant. Driving without proper levels of coolant/antifreeze may cause a coolant system failure. Cooling system leaks. A broken water pump. Radiator issues. Oil too low. Thermostat failure. Issues with the belts and hoses. Heater core is plugged up.
