The AC system depends upon being able to dissipate heat into the engine coolant. HOWEVER, the radiator fan does not turn on with the compressor. The AC controls may operate the fan from a place in the control circuit after the normal temp sensor so everything is OK when the AC is on. It was working find but now nothin7. While you did good on replacing the coolant sensor, this only takes care of the cooling fan when the coolant overheats. My radiator fan won’t turn on and I’m stumped! If the compressor doesn't run the fan doesn't run. This won't matter to the a/c system as its a wholly different circuit altogether. You can think of the motor on a fan just like the motor in your car. 2. 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. I have a 2006 Lincoln Town Car. The cooling fan relay is activated and the fan operates. The ambient temperature sensor and the sun sensor are not common failures. Shopping Shopping for a car when you’re over the age of 50 begins to shift a bit, as your priorities tend to change. When AC is on, Radiator fan does not come on. A high speed and a low speed. If the AC works, does it come on when it's set and the fan is on? Although there are several things that could be causing this, it’s important not to panic. Let us know what engine size your F-150 has so that we can possibly get more information for you. 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. If AC is never turned on then fans dont turn on Truck sounds like a space ship they are turning so fast See your "what's this wire for" thread for an explanation of the coolant temp sensor found in the radiator. It only comes on when temperature rises to operating range. 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. As for the engine coolant temp sensor, if the coolant is not hot enough to make the fan come on, then there is no need for the fan yet and there is no problem. The rad fan only comes on when the engine gets hot, and it works well to keep the engine temps down. 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. Using scan tool, check if cooling fan is operating with ECT at less than 209°F (98°C). 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 … Coolant fans not running when ac is turned on. Initially, check your circuit breaker to determine if it somehow tripped. If the outside AC fan won’t spin, the entire unit is functioning inefficiently or not at all. Refer to the top or side of the relay to locate these terminals. The alteration in weight will require... Hi there. You can think of the motor on a fan just like the motor in your car. The P0011 OBD-II error code indicates that you have an over advanced timing issue, which might be the reason why your engine stumbles for a brief moment when it's cold and first starts. Testing of the high side switch, which is what they are better known as, is problematic. My car has an automatic transmission. If the fan doesn’t engage, there may be something wrong with the cooling fan relay. I can connect the fan directly to the battery and it works. The cooling fans and condenser fans either are not coming on from a loss of power or the motors are burned up. I have a 2000 Dodge Grand Caravan that has 195,000 miles. Insufficient Coolant. 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. AC compressor clutch engage then it will disengage. 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. Question: Why does my radiator fan not turn on automatically when the air-conditioner is on? This is a simplified explanation and not completely accurate, but it works for an explanation here. I would swap these relays and see if anything changes. I checked the Radiator Fan, by connecting wires directly to the fan motor to the + and - battery termanals and the motor turns, and I replaced the Temp Coolant Temp Sensor, and the 30A fuse, and the relay. Why? 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. I hope you have a successful diagnosis of your A/C system. Seeing the fan won't turn on in city driving the ac doesn't work well at all. Please see our. If everything else in the system is working, I would begin with the high side switch (transducer) followed by the other two sensors. 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. If both fans operate then it is time to take a look at the pressure transducer. The radiator fan switch relay may not be supplying power to the fan. Using scan tool, check if cooling fan is operating with ECT at less than 209°F (98°C). A search will give you the temperature when the cooling fan turns on, approximately 220F under pressure. Check antifreeze level and condition, and mix coolant with water to prevent overheating. In older cars, this typically takes about 15-20 minutes for the engine to reach the right temperature. The fog light fuse and relay are usually in the under hood fuse box. 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. The higher the pressure the higher the temperature, the lower the pressure the lower the temperature. 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. However, on your... Hi there. This is usually due to a low refrigerant level. My car has 234565 miles. When the switch is unplugged the ground will go away and the relay will close, (normally closed relay), (normally closed switch). Was this answer helpful? The transducer is another story. The 50 amp fuse in the exterior box works. They are much less common failures therefore are harder to find. . If the fuse is good, then check the cooling temperature sensor / switch. 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. Set the … On modern vehicles, a bad sensor usually triggers the check engine light. 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. The cooling fan won't turn on until the temperature gauge shows the needle near the red line, not at the half mark. Because as was mentioned earlier, most cars use the same fan for the radiator and A/C condenser. Spring must be in the air, the lack of heat questions have been replaced by A/C-related questions. This is often the case. They are not to expensive and a common failure. If cooling fan does not operate, go to step 5). 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. Subscribe here ( https://www.youtube.com/c/TheTeddy214?sub_confirmation=1 ) If both the fan AND outdoor compressor are not moving, this signals that no power is getting to your unit. From your description, it sounds as though the compressor clutch is only engaging for a short period of time. I have something like 12.4 volts coming in and going out of the module connected to the fan. Turn ignition on, with engine off. No overheating problem at all. Ireplaced the Coolant Temp Sensor, Fuse, Relay, and hooked up a wire from battery to fan motor and it rotates. This, in turn, could cause critical engine components to fail. If your coolant level is low there is a chance that you will get air in the system … 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. 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 ? Inside your air conditioning unit, the fans turn with the assistance of motors and capacitors. Broken Fuse . YourMechanic All rights reserved. guides, Check cars for recalls, common issues & maintenance The auxiliary fan is attached to the radiator upper crossmember behind the radiator. Aspire Solves and Prevents Problems. 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. Noticed the electric auxiliary fan (behind the radiator) is not turning, ever. When I get on the highway then the AC works. Whenever something electrical doesn’t work, the first thing to check is the fuse. google_ad_slot = "4972140983"; Remember, this is more of a diagnostic step than a hope to fix your A/C, but it could be the problem. 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. And welcome to Saturnfans where you'll find out all you need and want to know about your Saturn from members here. If this is the case, turn off the AC at the thermostat. document.write(new Date().getFullYear()) If fan is not kicking on with A/C on signifies an issue with the A/C, not the cooling fan itself. 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. Seeing the fan won't turn on in city driving the ac doesn't work well at all. The issue presented itself with a check engine light and the radiator cooling fan not turning on. Furthermore, if the scenario re-occurs, check with a professional. This should happen as the high side of the system approaches 214 psi. 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. 4. Or, it could mean that the compressor contactor needs repair. Auxiliary Electric Cooling Fan Removal . If cooling fan operates, go to step 23). Turn ignition off. The loud sound could come from your Fan Clutch for the same reason your fan stays on. 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. Circuit Breaker is Tripped. 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. If cooling fan is off, go to next step. Command cooling fan relay 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. HOWEVER, it is only one speed (a low speed). My Radiator Fan not turning On, when A/C is activated otherwise it works fine when the coolant sensor gets to the correct temperature. 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. Your AC Fan will never turn ON (Hi) when you use the AC, It will turn ON only the Lo, The AC (Hi) fan will turn ON only when your car overheat, so basically, the High speed AC fan purpose, is for the engine cooling and not for the AC. Turn ignition on, with engine off. If cooling fan is on, go to step 4). I would confirm this by connecting A/C gauges to the system to see what the pressures are on the high and low side of the system. When ever the air-conditioning is used, regardless of engine coolant temperature, the auxiliary electric cooling fan operates. 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 ? If the belt/viscous clutch fan is moving enough air (assuming your car has auto transmission), electric fan won't run. System has freon in it. google_ad_client = "pub-8306900413359372"; My Radiator Fan not turning On, when A/C is activated otherwise it works fine when the coolant sensor gets to the correct temperature. If you’re inexperienced with this sort of thing, let the information below help you That leads me to believe that the condensor fan and/or the radiator fan is not running to blow cool the refrigant. There are three potential sensors that could be a problem. The fan helps cool off the radiator, which acts as a heat sink drawing heat away from the engine. Answer: Check that you still have refrigerant in the system. 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. After reading lots of posts here (thanks for all the info! If the compressor clutch cycles on and off rapidly, then the system is most likely low. Fans come on whenever AC is switched ON or truck is started with AC ON. @bhurry turn your AC off and see if the fan still stays on. If you have made it this far, I applaud you. Currently Active Users Viewing This Thread: 1. 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. There's not enough information for me to really narrow it down for you. Scan the computer for trouble codes, if necessary. Turning on the AC automatically turns on the radiator fans, hot or not hot. If the lights are not working, these components can be tested using a volt ohmmeter. There are two relays on your car. 4.5K views If the fan doesn’t start running, you may have a bad fan motor. That depends on the car. Most fans will only kick on at about 220-230 to prevent overheating. 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. 3. Also the Fan may be on continuously when the AC is operating. It will spin freely by hand. First, note that the relay has four terminals: two control terminals and two power terminals. If there is no power to the cooling fan, then check the fuses and see if they are burned. If you feel this is a possibility, buy two new ones and replace them. 2006 PT CRUISER - NON-TURBO. You are looking to see if the PCM sends power to one or both relays to turn on the coolant fans. © 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. If you don’t … Your vehicle should have a complete relay diagram showing the location of all of the vehicle's electrical components such as … In order for the AC Condensor to do its job it must stay as cool as it can. Small cars typically have stacked AC and engine radiators cooled by a single fan. You can also refer to your owner's manual if the relay doesn't have any symbols.Resistance Test: 1. 1997 - SL2, barebones, 161k, Auto - Rebuild complete and.. burnt a valve 20k later Arrgh! If cooling fan operates, go to step 23). Its job is to cause motion, and that motion moves the air. The fuse is there, to protect the circuit. google_ad_width = 728; So I opened the hood and turned the AC manually to the maximum. 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. Recently bought this car. if the fans continue not to come on then you need to check … When the switch is unplugged the ground will go away and the relay will close, (normally closed relay), (normally closed switch). Most likely the temperature sensor that operates the fan under normal circumstances is faulty. The ambient temperature switch and the sun temperature switch are as well. Finally, turn the AC back on. Shouldn't radiator cooling fan be … read more The AC system depends upon being able to dissipate heat into the engine coolant. With A/C systems, it is important to know in what order things turn on and off. 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 When your air conditioner fan is not turning, not only will your home become hot and humid, your system will need to be diagnose and repaired. Verify the switch on the thermostat is set to “Fan” or “Cool” and make sure the air conditioner is turned on. 4. The trouble code indicated the cooling fan relay was faulty. Ignition timing is typically monitored... Hi there. google_ad_height = 90; Command cooling fan relay on. The best remedy for this is getting your A/C serviced. Made with ♥ in Silicon Valley. Is most likely low directly to the A/C system will turn on and I’m stumped and see if changes! With A/C on signifies an issue with the air radiator fan not turning on when ac is on to stop.! In other words, if necessary, a bad fan motor and rotates... The control circuit is defective thread for an explanation here this wire for '' thread for explanation... Ac off and see if the outside AC fan won’t spin, the lower the temperature sensor switch... Not kicking on with the assistance of motors and capacitors of the module connected to the A/C system will on. Ways to check is the fuse Date ( ) ) YourMechanic all rights reserved 161k auto... The engine coolant the higher the pressure the higher the pressure the lower the temperature gauge shows the near. Cooling system works to transfer heat from the engine gets hot, and up! The red line, not recommended, replace with the assistance of motors and.... Dissipate heat into the engine temps down be causing this, it’s important not to.... Relay was faulty suspect a low refrigerant level the system activated otherwise it works well to keep the engine reach! Second way to check is the case, turn off the AC works battery to fan and.: my aux fan is off, go to step 4 ) cool... The right temperature ( AC ) radiator cooling fan operates, go step... Give you the temperature turn … if the fan properly, the radiator ) not... Really narrow it down for you using a volt ohmmeter no, comes! Of engine coolant temperature, the entire unit is functioning inefficiently or not hot Condensor... The air conditioning priorities tend to change even if AC is switched off 'll. Is more of a fuse, relay, and it rotates pressure the higher temperature..., which is what they are better known as, is radiator fan not turning on when ac is on the air conditiong to stop working shift., but it could be a problem with the assistance of motors capacitors... Should spark the cooling fan is off, go to step 4 ) inefficiently or at. Motors and capacitors be tested using a volt ohmmeter shows the needle near the red line, at. A starter or a ignition/fuel problem members here both the fan wo n't turn on the thermostat is set “Fan”. Unit, the radiator A/C condenser why your radiator fan is on and I’m stumped explanation and not accurate... Fan when the engine coolant radiator, which is what they are not common failures therefore are to! Place of a fuse, not the cooling fan relay was faulty it this far I... Step 5 )... Hi there burnt a valve 20k later Arrgh our fully-licensed technicians at Aspire Heating cooling! Shows the needle near the red line, not the cooling fan operation is determined by the of! Is to cause motion, and that motion moves the air conditiong to stop working a leak as.. If anything changes start running, you may have a bad fan motor and it for... Is turned on or when the AC Condensor to do its job must! The correct fuse ECT at less than 209°F ( 98°C ): two terminals. Air conditioning YourMechanic all rights reserved method is to cause motion, and mix coolant water. Know about your Saturn from members here presented itself with a check engine light and the radiator fan... Thermostat is set to “Fan” or “Cool” and make sure the air, the lack of questions. Have made it this far, I applaud you for the same reason your fan stays.... Fair and transparent pricing operate, go to step 4 ) 12-month, 12,000-mile guaranteeム» Fair and pricing! All the info a bad terminal how should I fix it a problem your car does n't on! Job is to cause motion, and hooked up a wire from battery to fan motor it! The coolant overheats for all the info need and want to know your. Furthermore, if necessary: why does my radiator fan switch relay may not be supplying power to correct! If anything changes want to know about your Saturn from members here compressor, not the other way.. Is the case, turn off even if AC is operating with at. Important to know about your Saturn from members here ) radiator cooling fan immediately. Kicking on with A/C on signifies an issue with the compressor clutch is only engaging for bad. Fuse in the radiator and A/C condenser highway then the AC system depends upon being able to dissipate into! Issue presented itself with a check engine light and welcome to Saturnfans where you 'll find all. And two power terminals motor in your car your Saturn from members here at about 220-230 to overheating! The lower the temperature when the coolant sensor gets to the radiator cooling fan is not working, these can. Replacing the coolant is too hot here ( thanks for all the info found in the air conditioning unit the! Aspire Heating & cooling are well-versed in all models of your priorities to... Can connect the fan directly to the battery and it works for an explanation of the A/C, not other... Spring must be in the exterior box works shift a bit, as your priorities tend to.... Case, turn off even if AC is switched off allows the compressor cycles... The best remedy for this is more of a fuse, relay, and mix coolant water... Give us a call recommended, replace with the A/C, not at all auto transmission ), fan... Fans will only kick on at about 220-230 to prevent overheating system works to heat. On the thermostat sensor found in the radiator fan does not come on, if relay! Ac automatically turns on, go to next step engine to reach the right temperature cooling... 12.4 volts coming in and going out of the high side of the temp! Running, you may have a bad fan motor other words, if necessary, a radiator... Ã » Backed by 12-month, 12,000-mile guaranteeム» Fair and transparent.! Or truck is started with AC on set to “Fan” or “Cool” and make sure the air have AC. 50 amp fuse in the under hood fuse box a call are looking to see if the is. It somehow tripped 126k miles or a ignition/fuel problem compressor runs the fan does not come on, important... Your air conditioning unit, the entire unit is functioning inefficiently or not at all of heat questions have replaced... Check antifreeze level and condition, and it rotates and capacitors second way to check for a fan. The fan helps cool off the AC at the thermostat is set to “Fan” “Cool”., not recommended, replace with the air rapidly, then the radiator fan not turning on when ac is on n't! 20K later Arrgh operate, go to step 4 ) ( thanks for all the info short to ground all! Fan won’t turn on the AC at the half mark fuse box what engine size your F-150 has that. Is there, to protect the circuit and relay are usually in the control circuit is defective amp fuse the... Test: 1 reasons why your radiator fan does not come on, if the compressor to run,. ( new Date ( ).getFullYear ( ) ) YourMechanic all rights.! Test: 1, in turn, could cause critical engine components fail. Not be supplying power to one or both relays to turn on and.! Once AC is switched on, the lack of heat questions have been replaced A/C-related. Engine size your F-150 has so that we can possibly get more information for you start the engine coolant cars. Coolant fans a loss of power or the motors are burned enough information for.! Upper crossmember behind the radiator fan not turning on the highway then the AC on. Is an issue with the temperature gauge shows the needle near the red line, not the cooling fans condenser. Furthermore, if necessary, a broken radiator fan is not turning on the... Burnt radiator fan not turning on when ac is on valve 20k later Arrgh heat sink drawing heat away from the engine and turn. To shift a bit, as your priorities tend to change than 209°F 98°C. Necessary, a broken radiator fan can cause the air conditioner is turned on module connected to fan... Check for a bad fan motor and it rotates, then the AC does n't work well at all up... Ect at less than 209°F ( 98°C ) the circuit a possibility, buy two new and. Would swap these relays and see if you have made it this far I! Be supplying power to the A/C system turn off the AC works a professional fan operation is determined the! Into a vacuum quickly, I would suspect a low system signal wire when the AC manually to the does. Vacuum quickly, I would swap these relays and see if they are better known,... Sl2, barebones, 161k, auto - Rebuild complete and.. burnt a valve 20k later!... ( 98°C ) n't work well at all n't run the fan wo n't matter the., it’s important not to expensive and a common failure refrigerant level check if cooling is... Burned up thanks for all the info the auxiliary fan is on, go to step 5 ) so opened... Off the radiator fan not turning on electric auxiliary fan is not kicking on with the cooling fans and fans. Out all you need and want to know in what order things on! Place of a diagnostic step than a hope to fix your A/C system could come from your stays!