The fan keep running after switching off is a safety measure when the ECM cannot read the temperature it will keep the fan blowing for 10 to 15 mins after you switch off to make sure the car is not in a situation where it can cause a fire (as the ECM cannot determine if the engine is ice cold or burning hot).
How to diagnose a constantly running fan?
Volkswagen Jetta Radiator Fan Not Working Causes
- Wiring. The first thing that you would want to do is locate the fuse for your Jetta’s radiator fan and make sure that it hasn’t blown.
- Engine Temp Sensor. Your engine temperature sensor is responsible for relaying your engine temp to the ECU. ...
- Low Coolant. ...
- Fan Clutch. ...
Why does a fan remain running after ignition shut off?
When the engine is turned off, the coolant doesn't circulate, and the heat stays trapped, therefore prolonging the engine from cooling. Running cooling fans help cool down the engine even after you turn off the car. If your cooling fan runs for over 10 minutes after turning off the engine, you may have a problem that needs to be fixed.
How to tell if fan is running?
Reasons to Use Your Ceiling Fan In The Winter
- Redistribution of warm air makes a room feel warm and more comfortable to you and your family.
- Save up to 15% on heating costs.
- Reduce the cost of heating fuel.
- Reduce clutter and electric hazards due to space heaters and heating blankets.
Why does my car fan keep coming on?
Radiator fan runs full speed immediately upon car starting, does not slow down
- daveshea. I am a new owner of a 2010 C300 4Matic that I bought from an insurance auction - the car was a salvage car due to a front impact.
- JimPap. I'm not a Benz mechanic so what I'm stating is from an experience I had on my 2008 C300. ...
- 1625guesswho. ...
- michail71. ...
- 1625guesswho. ...
- television. ...
- daveshea. ...
- michail71. ...
- daveshea. ...
- Benz mec. ...
How does a cooling fan work when a car is turned off?
When the engine is running, the coolant circulates and flows to the radiator, where heat is dissipated. When the engine is turned off, the coolant doesn't circulate , and the heat stays trapped, therefore prolonging the engine from cooling. Running cooling fans help cool down the engine even after you turn off the car.
What should I do if the engine fan never turns off?
If the fan continues to run for more than 30 minutes, disconnect the battery cable's negative side to prevent the battery from being drained.
What does it mean when a fan turns off?
If the fan turns off, that means the relay is at fault.
How long does a cooling fan run after turning off a car?
It is ok for the engine cooling fan to keep running for a few minutes after turning off the car. Your car fan will run for a few minutes after you turn off the car then turn it off.
Why does my radiator fan keep running?
The situation when the car radiator cooling fan keeps running constantly can be caused mostly by a failing coolant temperature sensor or its wiring, broken fan start relay, damage to the electrical wires, electronic engine control unit (ECU) problems.
Why does my fan not work?
With such a problem, the fan may not work continuously, but for a fairly long period or it will often turn on and off.
Why does my radiator fan turn on?
Most often, the radiator cooling fan turns on constantly due to a short circuit in the starting relay or its wiring. The rest of the problems are less frequent. Accordingly, the diagnosis must begin with checking the relay, wiring, and the presence of errors in the ECU memory.
What happens if the sensor goes wrong?
If the incorrect information goes from the sensor to the ECU (an overstated or understated signal, its absence, a short circuit), then errors are generated in the ECU, as a result, the electronic control unit switches the engine into emergency mode, in which the fan “works” constantly so that there is no overheating engine. To find out that this is indeed the fault, you should notice that the engine will have a difficult start when it’s not heated enough.
What temperature does a radiator fan run at?
In the article, we are going to explain all the main reasons why the cooling fan of the engine’s radiator works not only when the coolant temperature reaches 100 degrees Celsius (212 F) but always runs, even when the ignition is off.
How to check if fan wires are damaged?
Therefore, you just need to find the spot where the wire is damaged. This can be done either visually or with a multimeter. Alternatively, insert two needles into the contacts of the tokens and close them together. If the wires are intact, the ECU will give an error of motor overheating.
What is the power supply for a fan?
For most cars, the fan power supply consists of “plus” from the relay and “minus” from the ECU in terms of temperature from the coolant temperature sensor. “Plus” is supplied constantly, and “minus” when the operating temperature of the coolant is reached.
Why does my blower motor keep running after I turn off the car?
Why does the blower motor keep running after I turn off the car? If your car uses a blower motor controller, it can keep running the blower motor after you shut down the engine. Those used to be installed only on vehicles with automatic climate control with variable speed fans, but now they’re installed on many late model vehicles.
Why are blower motor resistors bad?
The downside of blower motor resistors is that, in order to reduce voltage, a resistor converts the energy into heat. These days cars can’t afford to waste that energy—there are simply too many electrical accessories to run.
How a blower motor controller differs from a blower motor resistor?
In a vehicle equipped with a blower motor resistor, voltage is reduced by the value of the each resistor based on the position of the fan switch. The lower voltages result in lower fans speeds. The downside of blower motor resistors is that, in order to reduce voltage, a resistor converts the energy into heat. These days cars can’t afford to waste that energy—there are simply too many electrical accessories to run.
What is a blower motor controller?
The blower motor controller is a solid state device with a power switching transistor that takes its marching orders from the HVAC control head. In some cars the signal from the HVAC unit to the controller is digital, while in others it’s pulsed or a varied voltage.
How long should a car fan run?
That is probably normal. The car fan will run until the sensor detects that the coolant temp has dropped enough. Also, some car fans are programmed to run anyway after engine shut-off, to eliminate “heat soak”, where the heat from the engine would otherwise cause possible damage to other components under the hood. The fan should never run longer than a few minutes max, however. If it does, the relay that turns it on is probably stuck and the fan will run down your battery in short order.
Why does my radiator fan cut off?
The radiator fan runs on the temperature of the water in the radiator. If the temperature is too high then it runs to cool the water & when the temperature of water drops less than the set temperature then the fan cuts off immediately.
Why does my car overheat when the fans are on?
It's common to think you might have a bad relay or fuse. If either of those is the case, your fans wouldn't turn on and it will cause your car to overheat.
Where is the fan timer located?
The fan timer module is located in the driver's side foot well of your car (just below the steering column). If you look right above the fuse box, you can see the module, which is about the size of a deck of playing cards. It allows the fan to stay on after the car has been turned off for additional cooling.
How much does it cost to replace a fan switch?
If the cooling fan switch is not working, it is easy to replace yourself. A new one will cost you around $30.
Why do mini cooper fans stay on?
Mini Cooper fans are meant to boost the circulation of air around the radiator to ensure the engine cooling system is well cooled. The mini copper fans should speed up the process of cooling by driving fresh air into the radiator. Why does your Mini Cooper Fan stay on when I turn off the engine? The answer is simple; there is something wrong with the fan or the cooling system.
What does it mean when a low speed fan is broken?
In case it is broken then it means that it does not come on when it is supposed to, therefore, the high-speed fan will have to kick on at a high temperature and will stay on even after parking.
Why is my car low on coolant?
The most common cause is the coolant expansion tank failing. Fixing this problem is easy. This is not an expensive repair. Additionally, you need to check the thermostat housing.