A mechanical fan WILL spin as long as the engine is running, but it will only 'lock up' when needed. Depending on the wiring setup of the vehicle, this may cause them to stay on even when the vehicle is off, which will drain the battery. The fan deffo wasn't on when I turned the engine off. The trigger is the thermostat in the radiator of your vehicle. The second is the fan switch itself, the sensor which tells the relay when to activate the fan. The length of time cycling on and off seems to correlate to the temperature. I have a 2000 Boxster S, and after completing the heater box foam repair and properly purging cooling system I noticed that my radiator fans did not come on when operating temp was reached, but they do work when AC is in operation. Rising Temperature Gauge. And I turned the ignition back on to see if the fan powered up. Engine overheating. If there’s an issue with the relay, the fan will be affected. By continuing to use this site you consent to the use of cookies as described in … The cooling fan should come on immediately or within the next couple of minutes. A cooling fan relay is used on vehicles that have an electrical fan to cool the engine. Most fans should come on when the coolant reaches about 200 to 230 degrees. Even though it’s called “water cooling”, the fans still play an important role. Also, most cars will run the fans at a high speed if the A/C is turned on. If it’s not working, the fan won’t turn on when it needs to, which means the engine might overheat. If the a/c button is on than the chances are the fan will be on as well, even if a/c is off the fan should still come on only when it needs. Once the temp gets so hot, the ECU commands the radiator fan to come on. What are the names of Santa's 12 reindeers? If it does kick in then your low speed fan resistor has failed. In older cars, this typically takes about 15-20 minutes for the engine to reach the right temperature. If this is your first visit, be sure to check out the FAQ by clicking the link above. I tried disconecting the battery for a couple hours and it goes back to running normally, but this start doing it again after driving for a couple weeks. No Whirring Noise from the Engine Bay. The cooling fan relay essentially functions as the switch for the engine's cooling fans, and is therefore an important electrical component of the vehicle's cooling system. As andyl says, Fuse F35 provides power to the Engine Cooling Unit & Fan. This is because the engine needs air to keep it at the optimal temperature. You need to get the temp up to about 116 degrees to see if the high speed fan to kicks in. This time turn on the ignition for a little longer and then t urn it off. It may cause the fan to cut in and out, or not … Your radiator fan should kick in at about 200 degrees Fahrenheit. Should either of these parts fail – the thermostat or the switch – your radiator fan will not turn on or off and this spells serious trouble. At higher coolant temperatures, the switch closes to start the cooling fans. No, only comes on when the coolant is too hot. When the radiator fan stops working, the coolant does not cool down. A temperature-sensitive switch functions to turn the fan on and off periodically. Simple aftermarket fix, about £20 for all … Your vehicle's cooling system is crucial to its performance, and every time your engine overheats, you cause damage. If the fans do not come on and the engine overheats turn off the engine. On vehicles with air conditioning, rising refrigerant pressures will also activate the cooling fans. ¿Cuáles son los 10 mandamientos de la Biblia Reina Valera 1960? If you get the on at 185 and off at 165 when the coolant got to 185 the fan would come on to assist and this is what would be recommended. Unplug the electrical connector for the cooling fan motor located on the bottom of the fan motor. Keeping noise levels down is important, but should always come second to keeping your system safe. The radiator fan turns on at cold startup. Some fans and cases even come with manual switches for basic fan … Any time the coolant temperature rises to higher than normal levels, the fan will start and continue to run until coolant temperature returns to a normal range. Turn ignition back on, do not start the engine. The coolant may not be moving due to a water pump problem, blockage in the radiator or hoses, or a stuck valve, i.e., the “thermostat” in the coolant line. Thread for an explanation of the engine needs air to keep the radiator fan keeps your engine overheats, can... 12 reindeers the radiator $ 789 State Route 59, Shorewood, Illinois 60404 come second to your. Are much quieter damage associated with overheating, and every time your engine overheats, you now. 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