. If the fan does not come on, something in the control circuit is defective. In other cases, the switch will turn on and stay on well past the cooling temperature threshold, resulting in the fan running even when the engine is off. ttou68 Active Member Verify the switch on the thermostat is set to “Fan” or “Cool” and make sure the air conditioner is turned on. 4.5K views With A/C systems, it is important to know in what order things turn on and off. 1997 - SL2, barebones, 161k, Auto - Rebuild complete and.. burnt a valve 20k later Arrgh! If the belt/viscous clutch fan is moving enough air (assuming your car has auto transmission), electric fan won't run. The fan helps cool off the radiator, which acts as a heat sink drawing heat away from the engine.

radiator fan not turning on when ac is on

However, on your... Hi there. The cooling fan relay is activated and the fan operates. Most fans will only kick on at about 220-230 to prevent overheating. 2. 2006 PT CRUISER - NON-TURBO. At this point I would just replace the transducer, which is mounted near the bottom right of the radiator in the high side of the A/C system. The 50 amp fuse in the exterior box works. My Radiator Fan not turning On, when A/C is activated otherwise it works fine when the coolant sensor gets to the correct temperature. You can think of the motor on a fan just like the motor in your car. So I opened the hood and turned the AC manually to the maximum. Currently Active Users Viewing This Thread: 1. If this is the case, turn off the AC at the thermostat. costs, Hand-picked, community-rated professionals, Explore nationwide job opportunities for automotive document.write(new Date().getFullYear()) The ambient temperature switch and the sun temperature switch are as well. If fan is not kicking on with A/C on signifies an issue with the A/C, not the cooling fan itself. The fog light fuse and relay are usually in the under hood fuse box. If you have determined the system is full and the fans do indeed operate, you will need to figure out if a sensor has failed or if the relays themselves have failed. If cooling fan is on, go to step 4). It was working find but now nothin7. And this is what the compressor does, it compresses one side of a calibrated valve while it sucks the other side into a low pressure therefore creating a low temperature that you will feel in the cabin. Fuse. Turn ignition off. If your coolant level is low there is a chance that you will get air in the system … If everything else in the system is working, I would begin with the high side switch (transducer) followed by the other two sensors. If AC is never turned on then fans dont turn on Truck sounds like a space ship they are turning so fast Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing. Furthermore, if the scenario re-occurs, check with a professional. The ambient temperature sensor and the sun sensor are not common failures. If cooling fan operates, go to step 23). OK then what i would do is check the fuse i mentioned and make sure its good, then find the temperature switch located on the radiator and pull off the connector. Keep in mind, our fully-licensed technicians at Aspire Heating & Cooling are well-versed in all models of … A high speed and a low speed. A search will give you the temperature when the cooling fan turns on, approximately 220F under pressure. When AC is on, Radiator fan does not come on. Don’t let this strange name fool you, it is simply a sensor that relays the amount of pressure in the system to the PCM and the PCM decides when to turn on the fans and or compressor clutch. Bingo, after a while BOTH radiator fan and condensor fan stopped running (high speed or low), and then for 30 sec of so, they will try to spin … There are three potential sensors that could be a problem. Testing of the high side switch, which is what they are better known as, is problematic. This part can get really complicated, but the first thing to do is run the A/C with gauges connected to observe the system pressures and monitor the circuit from the PCM to the relays. There's not enough information for me to really narrow it down for you. Insufficient Coolant. If the fan doesn’t engage, there may be something wrong with the cooling fan relay. If it exceeds this amount of pressure and the system doesn’t turn on, one of the sensors in the system that the PCM uses to know when to turn the system on and off has failed. Good luck. The best remedy for this is getting your A/C serviced. You are looking to see if the PCM sends power to one or both relays to turn on the coolant fans. Why? If cooling fan operates, go to step 23). If the outside AC fan won’t spin, the entire unit is functioning inefficiently or not at all. Answer: Check that you still have refrigerant in the system. Inside your air conditioning unit, the fans turn with the assistance of motors and capacitors. If the AC works, does it come on when it's set and the fan is on? This should happen as the high side of the system approaches 214 psi. If the fuse is good, then check the cooling temperature sensor / switch. The issue presented itself with a check engine light and the radiator cooling fan not turning on. First check the cooling fan circuit. The scanner you have, and many other aftermarket scanners and those insurance devices that hook up to the OBD connector, are known to cause various problems that can arise way after the tools are removed. If you can see the coolant line that is damaged, and can reach both ends of the hose, you should be able to replace the coolant line rather easily after removing the engine cover and air cleaner. On modern vehicles, a bad sensor usually triggers the check engine light. If cooling fan is off, go to next step. Your vehicle should have a complete relay diagram showing the location of all of the vehicle's electrical components such as … I hope you have a successful diagnosis of your A/C system. YourMechanic All rights reserved. /* 728x90, created 4/10/11 */ If you have made it this far, I applaud you. Answer: Check first the fuses and relays for the fan… If the lights are not working, these components can be tested using a volt ohmmeter. 2000 323i manual, with 126k miles. After reading lots of posts here (thanks for all the info! Optimize fleet uptime and compliance via mobile vehicle repairs, Partner with us to simplify and scale fleet maintenance, Over 25,000 topics, from beginner tips to technical No overheating problem at all. A little window washer fluid will not cause any damage to your engine or the cooling system, in fact it will actually make the system work a little better as the fluid has alcohol in it. If the high side spikes and the fans don’t turn on, I would suspect a problem with what is called the A/C pressure transducer (high side switch), one or both fan relays, the fan motors themselves, an ambient temperature switch or the sun sensor. This is usually due to a low refrigerant level. You can change the auto locking hubs to manual locking hubs as long as the parts will fit. The loud sound could come from your Fan Clutch for the same reason your fan stays on. owners, Our mechanics make house calls in over 2,000 cities, Fleet Maintenance with certified mobile mechanics, The statements expressed above are only for informational purposes and should be independently verified. The condenser fan (if it has a dedicated fan) or the radiator fan most always comes in (with AC on) when the compressor discharge pressure (or, alternatively, the liquid line one; look for where a sensor or a switch is located on the high pressure line) rises over an operative threshold. When the radiator fan does not work, this is a serious problem. I'd recommend having a mechanic come to you and check it out to see if you have a starter or a ignition/fuel problem. If cooling fan does not operate, go to step 5). If you feel like you need assistance with this, feel free to contact a certified technician who can diagnose your A/C system and make the necessary repairs to get it working properly once again. Made with ♥ in Silicon Valley. The trouble code indicated the cooling fan relay was faulty. Remember, this is more of a diagnostic step than a hope to fix your A/C, but it could be the problem. The auxiliary fan is attached to the radiator upper crossmember behind the radiator. It’s important to understand, in physics (AKA the world around us), there is a pressure temperature relationship that an A/C system is affected by. I would swap these relays and see if anything changes. The a/c system will turn on the cooling fan only if there's a sufficient amount of refrigerant that allows the compressor to run. Once AC is on and fans are running they do not turn off even if AC is switched off. This is often the case. This will require a wiring diagram. If the low side sucks into a vacuum quickly, I would suspect a low system. Small cars typically have stacked AC and engine radiators cooled by a single fan. Question: My aux fan is not working, how should I fix it? 3. Recently bought this car. The transducer is another story. My radiator fan won’t turn on and I’m stumped! Just keep in mind, by replacing the auto hubs with manual hubs, you will have to get out of the... Hi there. Ignition timing is typically monitored... Hi there. Command cooling fan relay on. FAN BLOWER NOT RUNNING ON A/C BUT RUN ON HEATER, and ALSO couldn't turn on the FAN from the thermostat, Need help, Please On 2020-08-22 by Anonymous My ac air blower went bad in my trailer but for the last 6 months it couldn’t keep up with temp l had it set on, will new one be able to keep up ? In other words, the system is low on refrigerant. The electric radiator fan is not turning on when the air conditioner is turned on or when the car gets hot. The cooling fan operation is determined by the condition of the a/c compressor, not the other way around. Basically, if the high side pressure gets too high in the high side of the system, the fans should turn on, if the pressure gets to low in the low side of the system, the compressor clutch should turn off. google_ad_width = 728; The Front Blower Motor Relay (also known as the AC Relay), located behind the junction block with a black connector, B05, is the culprit. Coolant fans not running when ac is turned on. Its job is to cause motion, and that motion moves the air. So, what you had stated that the temp gauge, at the half way mark, does not mean the fan is bad, The temp gauge has to go to 3/4 mark before the fan will kick in, why such at a high mark. If cooling fan is off, go to next step. See your "what's this wire for" thread for an explanation of the coolant temp sensor found in the radiator. HOWEVER, the radiator fan does not turn on with the compressor. If both fans operate then it is time to take a look at the pressure transducer. Aspire Solves and Prevents Problems. It will spin freely by hand. This is a simplified explanation and not completely accurate, but it works for an explanation here. Volume and pressure are two different properties of a gas, which the refrigerant in your A/C system is a gas when it is allowed to escape to the atmosphere. Search past threads about it. Set the … Your car doesn't overheat, that's why, your AC fan (HI) doesn't turn ON. I have a 2000 Dodge Grand Caravan that has 195,000 miles. Although there are several things that could be causing this, it’s important not to panic. There is no "direct" catalog interchange engine for your VIN because your present engine was installed at the factory with an engine specific computer(s), engine wiring harness, suspension (engine weights vary), and so forth. guides, Check cars for recalls, common issues & maintenance The cooling fans and condenser fans either are not coming on from a loss of power or the motors are burned up. From your description, it sounds as though the compressor clutch is only engaging for a short period of time. If once you power the relays in this fashion you find one or both of the fans don’t turn on, I would suspect a problem with the fans. If it's an old system, there could be a leak as well. Had a problem with the Air conditioner (AC) radiator cooling fan in my VW Polo 9N, 2003. Was this answer helpful? If the fan comes on when the AC is running at MAX, but doesn't run when the engine is hot, check the temperature sensor or switch that sends the signal to the computer or module to operate the fan. Ireplaced the Coolant Temp Sensor, Fuse, Relay, and hooked up a wire from battery to fan motor and it rotates. 3. System has freon in it. When the a/c is turned on and no compressor is heard/no cooling is felt then the cooling fan isn't needed so its left off automatically. OK the radiator fan switch will ground the relay in the J/B 2 on the left side of the engine comp, which also goes through the A/C high pressure switch causing the relay to hold contact open. When I get on the highway then the AC works. google_ad_height = 90; If the compressor clutch cycles on and off rapidly, then the system is most likely low. The fuse is there, to protect the circuit. If necessary, a replacement relay costs around $20.There are three ways to check for a bad terminal. If you’ve tried the above and you still have an AC fan not turning on properly, give us a call! Seeing the fan won't turn on in city driving the ac doesn't work well at all. The rad fan only comes on when the engine gets hot, and it works well to keep the engine temps down. It is unlikely both relays have failed at the same time, but possibly, one failed a time ago and now the other has as well. Question: Why does my radiator fan not turn on automatically when the air-conditioner is on? turn the car on, if the fans come on, then there is an issue with the temperature switch. Spring must be in the air, the lack of heat questions have been replaced by A/C-related questions. Using scan tool, check if cooling fan is operating with ECT at less than 209°F (98°C). If you feel the AC is not cooling as much as usual, cannot hear the AC clutch engaging, and see refrigerant leaks, you may have to recharge your AC. Refer to the top or side of the relay to locate these terminals. And welcome to Saturnfans where you'll find out all you need and want to know about your Saturn from members here. 2. Noticed the electric auxiliary fan (behind the radiator) is not turning, ever. If you have difficulty getting the blades to turn, there may be debris wrapped around the fan axle, or the motor bearings may be dirty or jammed. Check the temperature that has been set on the thermostat. In other words, if the compressor runs the fan runs. Radiator fan not turning on but will turn on when AC is on Discussion in ' Gen 3 Prius Care, Maintenance & Troubleshooting ' started by ttou68 , Apr 23, 2020 . That depends on the car. I have a 2006 Lincoln Town Car. While you did good on replacing the coolant sensor, this only takes care of the cooling fan when the coolant overheats. If the compressor doesn't run the fan doesn't run. © When the AC is switched on, the compressor clicks on. 4. There are two relays on your car. When I get on the highway then the AC works. If the fuse blows, there is a short to ground. Also the Fan may be on continuously when the AC is operating. Its job is to cause motion, and that motion moves the air. Finally, turn the AC back on. They are not to expensive and a common failure. Shouldn't radiator cooling fan be … read more You aren't the first nor will be the last to question why the gauge needle was calibrated to be near redline before the cooling fan turns on. 4. HOWEVER, it is only one speed (a low speed). Turn ignition on, with engine off. Scan the computer for trouble codes, if necessary. google_ad_client = "pub-8306900413359372"; If the compressor is running long enough to build heat in the high side of the system, and the cooling fans don’t turn on, I would begin finding the fan relays and add power to the appropriate circuit to see if the fans turn on at all. Shopping Shopping for a car when you’re over the age of 50 begins to shift a bit, as your priorities tend to change. //-->. If the fan does not come on, something in the control circuit is defective. In other cases, the switch will turn on and stay on well past the cooling temperature threshold, resulting in the fan running even when the engine is off. ttou68 Active Member Verify the switch on the thermostat is set to “Fan” or “Cool” and make sure the air conditioner is turned on. 4.5K views With A/C systems, it is important to know in what order things turn on and off. 1997 - SL2, barebones, 161k, Auto - Rebuild complete and.. burnt a valve 20k later Arrgh! If the belt/viscous clutch fan is moving enough air (assuming your car has auto transmission), electric fan won't run. The fan helps cool off the radiator, which acts as a heat sink drawing heat away from the engine.