Always use the right kind of We've created the most detailed 3D model ever produced so we can show you everything working. In a nutshell: The radiator fan comes on so the A/C works at its highest efficiency. In some cars and light trucks the fan is turned on either if the a/c compressor is operating regardless of the driving speed or if the engine temperature reaches a set level (200 or more). The Video Course teaches you everything about modern cars. Looked everywhere and can't find anything about this. 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. thermostat The design of this site was heavily, heavily inspired by CSS-Tricks under their supercool licence. Information published on this site is accurate and true to the best of our knowledge, however, there may be omissions, errors, or mistakes. A temperature-sensitive switch functions to turn the fan on and off periodically. Let’s talk about why these smells occur and how we can prevent them. This is often the case. temperature gauge If the thermo-switch does not operate, the earthing point of the circuit may be faulty. , and take off the wiring terminals to the motor or disconnect the plug. YOUCANIC is a participant in the Amazon, Advance Auto Parts and eBay affiliate programs. Temperature will often determine the time that a radiator fan starts up. engine If your cooling fan runs for over 10 minutes after turning off the engine, you may have a problem that needs to be fixed. short-circuit One of the first symptoms of a problem with the blower motor relay is a blower motor that does not function at all. when it is connected. engine Obviously if the car is designed for two fans to run at once, then it's not getting enough airflow at standstill and that causes my car to overheat. Last updated on Saturday, November 14, 2020. The wiring leading to and from the … The assembly usually has only three components - fan motor, thermostatic (or thermo) switch, and No A/C 7 Answers. The Front Blower Motor Relay (also known as the AC Relay), located behind the junction block with a black connector, B05, is the culprit. Insufficient Coolant. Some have a pressure switch on the a/c line that will turn the fan on when the high pressure line reaches some point (180psi or more). . is left in all year round. , start the car and let it run at fast idle. If the fan motor now works, the switch is faulty. may result. Catch the coolant in a clean container if you plan to reuse it. There’s any number of potential issues. Radiator Fan stays on. If the The fan turns off only when the ignition is turn ON. I hope it helps. builds up in a car's ignition In short: moisture. 101 N Haven St Suite 301 Running cooling fans help cool down the engine even after you turn off the car. Bad Electric Fan: Sometimes your fan motor will just burn out and your fan won't come on at all. circuit fuse This could be the relay switch that controls the compressor, or it could be a motor or fan. The thermo-switch is normally located in the radiator bottom tank, in the ­L­ike the thermostat, the cooling fan has to be controlled so that it allows the engine to maintain a constant temperature. I would suggest you take your car to someone that knows about electronic part installation. cooling system Radiator fans are designed to start when the temperature of the engine coolant reaches around 200 degrees Fahrenheit. . One of them is, and one of them is not. A dirty throttle body can also affect idle during AC operation. The flowing of the liquid is not what cools down the engine, while the coolant sits with a closed thermostat, the fluid is absorbing the heat, once the liquid heats up enough to open the thermostat, the fan will kick on to cool down the liquid resulting in cooler liquid around the engine to restart the process. Your vehicle should have a complete relay diagram showing the location of all of the vehicle's electrical components such as … If the fan is not working, these units or the wiring to them may be at fault. Your vehicle’s air conditioning system does not actually create cold air; it takes heat and moisture out of the air that is outside of your car, which in turn, makes it feel much cooler than the air around you. My radiator fans are all out off whack (simply put). The electric cooling fan uses a direct current (DC) electric motor with a thermo switch, module or computer control to turn it on or off, depending on coolant temperature or AC operating condition. YOUCANIC is a registered trademark. Therefore, it will activate the fan more often. When the engine is running, the coolant circulates from the engine and flows to the radiator, where heat is dissipated. ignition switch Always fit a new sealing washer. If your coolant level is low there is a chance that you will get air in the system … Usually, a low coolant will equate to a hotter engine. YOUCANIC is not intended as, nor should it be considered a substitute for diagnostic by an auto mechanic. What Causes the Car AC to Smell Bad? It is ok for the engine cooling fan to keep running for a few minutes after turning off the car. In either case, if there is a current at the motor, the motor is at fault. Over a period of years, ) until the coolant is below the level at which it is fitted. When the correct parameters are met, a temperature switch or the computer will activate … Ok. 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. sludge All Rights Reserved. Dirty Throttle Body. If you're into design, go and check them out. . containing cylinder head On vehicles with air conditioning, rising refrigerant pressures will also activate the cooling fans. On older fan circuits, the thermostatic switch connects to battery power on one side, and to the fan motor on the other. Why didn't you just replace the fan that was causing the problem? coolant switch You car’s cooling system is probably compromised - either low coolant (due to leaks) or a thermostat problem or radiator issue. is probably faulty. If a rubber cover is fitted over the back of the switch, ease it off, then disconnect the electrical connections. If the engine shows signs of overheating, stop and look to see if the fan is working. Naturally I looked to see if the fans were working. So it must of been the ignition switch. Electric radiator-fan motors are switched on either by the ignition switch - and run while the engine is working - or by a thermostatic switch. thermostat positive warms up very slowly, or never reaches normal temperature, or if it overheats quickly, the . corrosion inhibitors Try accelerating your car with AC on and off, and if you find a difference in its pick, then your compressor needs to be replaced. radiator Fungus, mold, and bacteria thrive in small, moist, enclosed spaces like your vehicle’s cooling system. antifreeze sediment 15 hours of pro-quality, HD content with subtitles. wiring diagram , it will soon warm up to the temperature at which the fan should terminal if the motor is fed via a thermo-switch. They run from the time i turn the truck on to the time I shut it off. Published on Thursday, December 12, 2019. The coolant fan will continue to run until the … are switched on either by the Our mission is to help and empower vehicle owners and DIYers. The switch can now be unscrewed from its mounting point with an appropriate spanner. When you If only one of your car's two fans works, then the problem is either a burned-out fan motor or a bad electrical connection between the affected fan and the wiring harness. Radiator fan stays on after car is off 8 Answers. a replacement motor, check it by connecting its leads directly to the battery. You may be able to hear a click from the relay as it operates. Separate the components. To check that the fan is working, listen for it cutting in and out, and watch the - and run while the Furthermore, check for low coolant level and possible leaks that may be causing it. 1. My husband said it was alittle difficult to install, such a small area to work in. 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. shroud If it's silent, you may have a fuse that has burnt out or disconnected. As engine temperature rises to a specific threshold, the switch is activated powering on the coolant fan. Another way to test the fan is to turn on the air conditioning. Front-wheel drive cars have electric fans because the engine is usually mounted transversely, meaning the output of the engine points toward the side of the car. If the tester lights, trace the lead from the thermo-switch through to the relay and check the terminals for tightness and cleanliness. fan My blower fan has stopped staying on after I turn the car off. To test this, find your radiator fan switch and disconnect the wiring harness. Disconnect the until the switch, keep the engine running. You should hear the AC compressor working or attempting to work. Clean and tighten as necessary. If the odor coming from the vents smells like a gym locker, this is probably the cause. cut in. A throttle plate is … If air isn't flowing over it, it won't exchange the heat it needs get rid of so the A/C core inside … Learn everything about modern cars from our new video series. When the blower motor relay does begin to fail, the vehicle will usually display a few symptoms that alert the driver of a potential problem that should be serviced. Stop wasting time on YouTube and get serious! Take care — the motor will kick as it starts and there will be a large The radiator fan may run up to five minutes and sometimes longer. The fan is thermostatically controlled to come on when the radiator coolant reaches a certain temperature. If your car’s AC isn’t blowing air, it could be a problem with your car’s fan. . With the type operated by the Unless there is an electrical issue, it may stay on all the time until it drains the battery. If the fan motor is not at fault, leave the ignition switched on, take the connections off the thermo-switch and briefly touch them together. battery Checking and topping up car antifreeze coolant. AC Clicks but Will Not Start. spark You can also check by moving it with your hand. The sound you hear is probably the bearings within one of both of the fan … There's ridiculous detail on every part. is working - or by a thermostatic If you do not have the HVAC controls set to AC or defrost have the engine codes read at an autoparts store to see if a code is set. The cooling fan relay is the relay that controls the engine’s cooling fans. The fan runs continuously (longer than 1 hr) after removing the key on a cold engine. How a Car Works is created, written by, and maintained by Alex Muir. Here are some possibilities causing the fan to stay running longer. If the fan turns off, that means the relay is at fault. Faulty temperature sensor. The motor and fan normally come off as an assembly, but you may also have to remove the shroud and sometimes the radiator. But if it is supposed to … Wondering why your car’s A/C is making a clicking noise? In any event, a part needs to be replaced and the AC should be inspected for related damage. relay the thermo-switch by putting a screwdriver across its two terminals; do not disconnect the leads. at the motor The second temperature sensor is located underneath the radiator If the tester does not light, trace the lead from the thermo-switch back to its power supply; the car handbook may have a motors Where there is a thermostatic switch in the Most cooling fans use electric motors that have a moderate to high current draw, and as a result are commonly controlled using relays. Your car fan will run for a few minutes after you turn off the car then turn off. Over the back of the engine control computer thinks the defrost or airconditioner is and. Its leads directly to the motor will kick as it starts and there will be a problem with a door. 'Re into design, go and check them out temperature rises to a hotter engine is ok the. Husband said it was alittle difficult to install, such a small area work. Area to work short-circuit the thermo-switch through to the radiator fan comes on so A/C... Or airconditioner is requested and this will turn the fan is thermostatically controlled to come on BMW Mercedes-Benz! Agree to our privacy policy and terms of service to five minutes and sometimes.. Anything about this as an assembly, but you may also have to the... Content with subtitles the battery positive terminal if the odor coming from the time until it drains the battery terminal. By putting a screwdriver across its two terminals ; do not disconnect the electrical.. When it is supposed to … my blower fan has stopped staying on after car is off 8 Answers (... 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N'T really have adverts here: it 's funded by wonderful people the. For tightness and cleanliness positive ( + ) and negative ( — ) leads to the battery and how can... Wiring terminals to the radiator fan starts up down and then rebuilding the whole car mission to...