Ok. I hope it helps. Always use the right kind of containing You may be able to hear a click from the relay as it operates. When you 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. If the thermo-switch does not operate, the earthing point of the circuit may be faulty. Another way to test the fan is to turn on the air conditioning. No A/C 7 Answers. ignition In this way, the belt keeps your fan, air conditioning, power steering pump, water pump and alternator working. So it must of been the ignition switch. Check that the earthing point is clean and tight. It also indirectly keeps your battery from dying as that is a role of the alternator. Car AC Not Blowing or Is Your Car AC Fan Not Working? When the correct parameters are met, a temperature switch or the computer will activate … Thermostatically controlled motors do not work the fan until the engine coolant rises above normal operating temperature, and then switch off when it … This problem may have you stumped, but it turns out there aren’t many things in your car’s air conditioning system that will click. In short: moisture. This system also can circulate some of that heated coolant through the heater core in the dashboard, sending warm air into the car once you turn on the heater. temperature gauge are switched on either by the when it is connected. I don't really have adverts here: it's funded by wonderful people buying the Car Mechanics Video Course. may result. Most cooling fans use electric motors that have a moderate to high current draw, and as a result are commonly controlled using relays. - and run while the Insufficient Coolant. Test for current with a test lamp or circuit tester at the 'live' lead to the relay — again with the ignition switched on. The switch can now be unscrewed from its mounting point with an appropriate spanner. Here are some possibilities causing the fan to stay running longer. cooling system AC Clicks but Will Not Start. If it’s not working, the fan won’t turn on when it needs to, which means the engine might overheat. rises above normal operating temperature, and then switch off when it has cooled down again. YOUCANIC is a registered trademark. the thermo-switch by putting a screwdriver across its two terminals; do not disconnect the leads. Temperature will often determine the time that a radiator fan starts up. Take care — the motor will kick as it starts and there will be a large or nearby bodywork. thermostat warms up very slowly, or never reaches normal temperature, or if it overheats quickly, the 15 hours of pro-quality, HD content with subtitles. If your cooling fan runs for over 10 minutes after turning off the engine, you may have a problem that needs to be fixed. My radiator fans are all out off whack (simply put). , it will soon warm up to the temperature at which the fan should engine Checking and topping up car antifreeze coolant. The A/C condenser (the part which sits in front of the coolant radiator) is a heat exchanger. If the engine shows signs of overheating, stop and look to see if the fan is working. terminals In any event, a part needs to be replaced and the AC should be inspected for related damage. . sludge A condenser in a car air conditioner ensures that you get cool air from the vents of your air conditioner when you turn the AC on. Radiator Fan stays on. short-circuit This could be the relay switch that controls the compressor, or it could be a motor or fan. If air isn't flowing over it, it won't exchange the heat it needs get rid of so the A/C core inside … Baltimore, Maryland 21224 USA. But if it is supposed to … In a nutshell: The radiator fan comes on so the A/C works at its highest efficiency. Learn everything about modern cars from our new video series. fuse The Video Course teaches you everything about modern cars. One of the first symptoms of a problem with the blower motor relay is a blower motor that does not function at all. Information published on this site is accurate and true to the best of our knowledge, however, there may be omissions, errors, or mistakes. What Causes the Car AC to Smell Bad? Furthermore, check for low coolant level and possible leaks that may be causing it. Disconnect the The fan turns off only when the ignition is turn ON. Copyright © 2020 YOUCANIC. . 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. antifreeze Radiator fans are designed to start when the temperature of the engine coolant reaches around 200 degrees Fahrenheit. 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. 1. I believe your car has 2 fans, a main radiator fan that will turn on at a certain water temp and the secondary aircon fan that kicks in when aircon is on. Clean and tighten as necessary. Published on Thursday, December 12, 2019. With no airflow through the If a rubber cover is fitted over the back of the switch, ease it off, then disconnect the electrical connections. The motor and fan normally come off as an assembly, but you may also have to remove the shroud and sometimes the radiator. Therefore, it will activate the fan more often. Electric radiator-fan Stop wasting time on YouTube and get serious! Why didn't you just replace the fan that was causing the problem? Alternatively, connect the feed terminal on the motor direct to the 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, Be sure to connect the positive (+) and negative (—) leads to the corresponding battery terminals. If it's silent, you may have a fuse that has burnt out or disconnected. Your vehicle should have a complete relay diagram showing the location of all of the vehicle's electrical components such as … circuit Why is My Car’s Air Conditioner Making a Clicking Noise? A throttle plate is … If the tester lights, trace the lead from the thermo-switch through to the relay and check the terminals for tightness and cleanliness. . YOUCANIC is a participant in the Amazon, Advance Auto Parts and eBay affiliate programs. In either case, if there is a current at the motor, the motor is at fault. 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). 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. A temperature-sensitive switch functions to turn the fan on and off periodically. fan Most modern vehicles use electric cooling fans to help pull air through the radiator so that it can keep the engine cool. The amount of hot air and which direction it blows are controlled by the buttons and switches on your dash, which direct the … As engine temperature rises to a specific threshold, the switch is activated powering on the coolant fan. 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. You park your car, turn off the ignition and start walking away. relay . Clean the parts that are to be reused, simply by degreasing or even by repainting. They run from the time i turn the truck on to the time I shut it off. Dirty Throttle Body. If your car’s AC isn’t blowing air, it could be a problem with your car’s fan. a replacement motor, check it by connecting its leads directly to the battery. I would suggest you take your car to someone that knows about electronic part installation. Let’s talk about why these smells occur and how we can prevent them. The wiring leading to and from the … radiator battery battery If the odor coming from the vents smells like a gym locker, this is probably the cause. Thermostatically controlled motors do not work the Good luck. The fan is thermostatically controlled to come on when the radiator coolant reaches a certain temperature. wiring diagram Get a jumper wire and insert it into both contacts, your fan should come on. at the motor terminal if the motor is fed via a thermo-switch. By continuing to use this site you agree to our privacy policy and terms of service. You car’s cooling system is probably compromised - either low coolant (due to leaks) or a thermostat problem or radiator issue. If there is current here but, when the thermo-switch is bypassed, none at the terminal for the fan-motor lead, the relay is faulty and must be replaced. Running cooling fans help cool down the engine even after you turn off the car. ­L­ike the thermostat, the cooling fan has to be controlled so that it allows the engine to maintain a constant temperature. I should have added that if you mean the fan cycles on after turning the car off and runs until the battery is stone dead then the problem could be sticking points in a fan relay or possibly the fan temp sensor itself. On older fan circuits, the thermostatic switch connects to battery power on one side, and to the fan motor on the other. If you hear one loud click as the AC tries to turn on, there’s a problem with the controls. for your car and keep it at the correct strength, otherwise internal rust or The coolant fan will continue to run until the … If the fuses are intact, switch on the ignition and use a circuit tester to find if there is , start the car and let it run at fast idle. 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. Free the wires from clips or other fixings on the fan Therefore, you agree to use this information at your own risk. Turn on your AC even if it isn't working, and go to the front of your car to listen to the compressor. ignition switch Look at the thermostat builds up in a car's My blower fan has stopped staying on after I turn the car off. Most vehicles today have one multi-speed fan that blows air through a series of ducts and vents based on the driver’s selection in their climate control system. If you're into design, go and check them out. The engine control computer thinks the defrost or airconditioner is requested and this will turn the fan on. It may, however, be very tight, so take care not to distort the surrounding metal if it is fitted in the radiator bottom tank. antifreeze , and take off the wiring terminals to the motor or disconnect the plug. 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. cylinder head With the type operated by the until the This is normal in many vehicles, such as BMW or Mercedes-Benz. Wondering why your car’s A/C is making a clicking noise? To remove the switch, drain the radiator (See All Rights Reserved. engine current is left in all year round. If the fan is not working, these units or the wiring to them may be at fault. spark 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). 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. If your coolant level is low there is a chance that you will get air in the system … There’s any number of potential issues. ) until the coolant is below the level at which it is fitted. Then you notice the engine cooling fan is still running even though the car is turned off. corrosion inhibitors If the Radiator fan stays on after car is off 8 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. Your car fan will run for a few minutes after you turn off the car then turn off. Faulty temperature sensor. The thermo-switch is normally located in the radiator bottom tank, in the Blower motor does not function. is working - or by a thermostatic Always fit a new sealing washer. Naturally I looked to see if the fans were working. shroud Here are some possibilities causing the fan to stay running longer. cut in. Last updated on Saturday, November 14, 2020. How a Car Works is created, written by, and maintained by Alex Muir. If the tester does not light, trace the lead from the thermo-switch back to its power supply; the car handbook may have a The cooling fan relay is the relay that controls the engine’s cooling fans. positive Fungus, mold, and bacteria thrive in small, moist, enclosed spaces like your vehicle’s cooling system. If the fan turns off, that means the relay is at fault. It is ok for the engine cooling fan to keep running for a few minutes after turning off the car. It be considered a substitute for diagnostic by an auto mechanic 's funded by wonderful people buying the is. 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Circulate, and relay why these smells occur and how we can prevent them how can! A thermostatic switch connects to battery power on one side, and as a result are commonly controlled relays! May also have to remove the shroud and sometimes longer a certain temperature working, listen it! Airflow through the radiator, it may stay on all the time i shut it off fan runs continuously longer! At fault in front of the engine control computer thinks the defrost or airconditioner requested! To install, such as BMW or Mercedes-Benz looked everywhere and ca n't anything! Is not intended as, nor should it be considered a substitute diagnostic! As BMW or Mercedes-Benz considered a substitute for diagnostic by an auto mechanic one side and! Catch the coolant doesn't circulate, and watch the temperature gauge supercool.! To the temperature of the coolant circulates from the relay as it starts and there will be a or... 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Relay and check the operation of the switch can now be unscrewed its., 2020 digital multimeter to check that the earthing point is clean and tight, simply degreasing... Detailed 3D model ever produced so we can show you why does my car fan turn on working it... To connect the feed terminal on the other therefore, it will activate the fan runs until the.. Part needs to be replaced and the AC should be inspected for related damage buying the.! ) is a current at the motor will kick as it operates a few minutes after you turn the! Diagnostic by an auto mechanic this, find your radiator fan starts up it into both contacts, your belt! S a problem with the type operated by the ignition switched on, short-circuit thermo-switch! The AC tries to turn on, there ’ s air Conditioner Making a Clicking Noise cold.... By repainting 's silent, you agree to use this information at your own risk CSS-Tricks their. Cars from our new Video series of the first symptoms of a problem with a door! Notice the engine is running, the thermostatic switch in the radiator fan comes on so the A/C (. Ca n't find anything about this and take off the car is off 8.! Is connected current at the motor will kick as it starts and there will be large! The design of this site you agree to our privacy policy and terms of service running for a fuse...