Once you turn off the engine, the car's computer senses that the radiator is at a higher temperature and still need to dissipate heat. When your car’s radiator fans keep running non-stop, it could mean a couple of different things. the ECT sensor and the ambient air temperature sensor.If the engine coolant temperature (ECT) sensor—located just below the distributor—begins to fail, it's likely that your fan will stay on for an extended period of time after the car's engine is shut off. Cooling fans stay on at all times. Coolant fan always running on my Focus The coolant fan on my car always runs even after a 10 minute drive.. Whenever something electrical doesn’t work, the first thing to check is the fuse. You're sitting in traffic, the light turns green, and you hope that traffic breaks fast enough for you to get some air flowing through the radiator so the temperature needle will go down. Until such time as you can either complete your checks of the circuits or take the car to a service facility, pull the fuse in the fuse relay box on the driver's side fenderwell. What's wrong with my cooling fan? The fan is … low coolant level, faulty coolant temperature sensor, PCM or ECU defective; coolant leaks from the water pump, cracked radiator, worn upper or lower radiator hoses, leaky heater core, leaky thermostat housing, rusted coolant bypass pipe, bad radiator fan relay, short in the electrical wires and so on. Often, the fan constantly runs if its negative wire is frayed. Ive seen cars do that-- usually hondas that I notice with fans running with vehicle off- no on inside. Electrical systems and relays control this process. level is too high in the engine compartment. So, if you are asking yourself, “Why does my car fan keep running?”, than read on to learn a bit more about this particular automotive problem and what you could probably do about it. Re: Radiator Fan keeps running, even after the ignition is off! It is a very common problem that results in radiator fan failure: the fuse may burn off … If a radiator gets too hot, it can crack, which is very bad news for your car, so it is a good idea to check this option first. Your email address will not be published. Depending on the engine, the wires can be located in different places. When you click links on our site we may earn an affiliate commission. A car lacking oil is not good. It also runs after I have turned the ignition off for about 1 minute. If you can trace a wire coming from the radiator electric fan all the way to a battery post or connection to the battery/electric of the car, then this means that a previous mechanic who didn’t quite understand the electrical engineering involved simply took a shortcut and avoided the configuration. If your coolant level is low there is a chance that you will get air in the system … In this case, the fan often runs constantly when the AC is on.eval(ez_write_tag([[300,250],'carphrases_com-leader-1','ezslot_7',108,'0','0'])); If it fails and the refrigerant leaks, the system “sees” that the radiator is overheating and tries to cool it down with the fan that is always on. If this is case, bring the vehicle to a different mechanic or an automotive electrical specialist. Cooling fan keep running 2 Answers. 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. The car stalls when braking. 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. I am getting great mileage and love the car, but this fan running is a downer. Click to expand... Only if you worry about the fan … Initially I thought this might be due to the extraordinary heat, but we've had a few cool days and I've continued to observe the behavior, even after short drives on which the engine is barely reaching its normal operating temperature. If the cooling fans are staying on at all times, this is another (less common) symptom of a possible problem with the cooling fan relay. Once you hook up the machine, it will give you the steps to retrieving the error message and interpreting the data. Though Ive never seen my fan continue running after shut off- here in So cal on a a hot day. Copyright © 2020 YourAmazingCar. Often, overheating can be fixed by adding coolant (if the coolant is low) or by changing the oil. See if the problem persists after taking this initial step. There are temperature sensors and some cars have separate sensors for the gauge itself. Usually, it is in the range + 87 and + 95 ° C (188 and 194 F). Another way to find out is to look at the data on the fan enable sensor located in the radiator. Over time, the clutch assembly will begin to wear and require servicing. A Bad Fuse. They have wired the fans directly into the power source with direct current, meaning they bypassed the relay and traditional electrical system of the car. Radiator Fan. Submitted: 11 years ago. This site uses Akismet to reduce spam.