Radiator fan running continuously when car is on.

[g3justin]

Have a 2009 Ford Fusion 2.3L, just did the thermostat (Fun!!) A few weeks ago As the engine was not getting up to Temp and sure enough thermostat was half stuck open. Up to now everything after that was fine, heats up fairly quickly and verified with the scan tool was running between 180 degrees and 190 ECT. Noticed today was taking a while to heat up, opened the hood and seen the radiator fan was runing it's 32 degrees out, I have the AC compressor fuse pulled as I don't want it running with the defrost, radiator fan never came on with the fuse pulled in defrost even before so honestly did not know if it worked or not till today. Anyways when you put it in windshield defrost the fan comes on now (can see the car knows it's 32 degrees out is the ambient temperature with the scan tool) figured the fan might still come on why now I have no clue, problem is when I turn off all HVAC the fan still stays running and keeps the engine around 170 so undertemp. Stays off as long as you keep the HVAC off defrost but once you go to defrostand then change it to any other setting or off the fan is on permanently to you turn off the car and restart it. Being it did not do that before, I'm leaning towards the fan control module on the side of the fan shroud? has anybody had similar symptoms to this with a bad controller? engine is not getting hot enough to engage the fan with no AC compressor running and did not up to recently. Any help would be appreciated thanks!. 

[bbf2530]

3 hours ago, g3justin said:

Have a 2009 Ford Fusion 2.3L, just did the thermostat (Fun!!) A few weeks ago As the engine was not getting up to Temp and sure enough thermostat was half stuck open. Up to now everything after that was fine, heats up fairly quickly and verified with the scan tool was running between 180 degrees and 190 ECT. Noticed today was taking a while to heat up, opened the hood and seen the radiator fan was runing it's 32 degrees out, I have the AC compressor fuse pulled as I don't want it running with the defrost, radiator fan never came on with the fuse pulled in defrost even before so honestly did not know if it worked or not till today. Anyways when you put it in windshield defrost the fan comes on now (can see the car knows it's 32 degrees out is the ambient temperature with the scan tool) figured the fan might still come on why now I have no clue, problem is when I turn off all HVAC the fan still stays running and keeps the engine around 170 so undertemp. Stays off as long as you keep the HVAC off defrost but once you go to defrostand then change it to any other setting or off the fan is on permanently to you turn off the car and restart it. Being it did not do that before, I'm leaning towards the fan control module on the side of the fan shroud? has anybody had similar symptoms to this with a bad controller? engine is not getting hot enough to engage the fan with no AC compressor running and did not up to recently. Any help would be appreciated thanks!. 

 

 

Hi justin, and welcome to the Ford Fusion Forum. I can not diagnose why the radiator fan seems to be constantly running.

 

However, just wondering why you are trying to disable the AC compressor when you have the HVAC system set to "Defrost"? Doing so will prevent your HVAC system from dehumidifying the air in the car, leading to difficulty in defogging the windshield and leading to all the windows eventually fogging up in many winter conditions. While we have had a mild winter in the Northeast so far, it will eventually lead to fogging/humidity issues.

 

Just something to think about.

 

Hopefully one of our tech members will jump in with some insight into your radiator fan issue.

 

Good luck with whatever you decide to do.

Edited February 26, 2020 by bbf2530

[g3justin]

2 hours ago, bbf2530 said:

 

 

Hi justin, and welcome to the Ford Fusion Forum. I can not diagnose why the radiator fan seems to be constantly running.

 

However, just wondering why you are trying to disable the AC compressor when you have the HVAC system set to "Defrost"? Doing so will prevent your HVAC system from dehumidifying the air in the car, leading to difficulty in defogging the windshield and leading to all the windows eventually fogging up in many winter conditions. While we have had a mild winter in the Northeast so far, it will eventually lead to fogging/humidity issues.

 

Just something to think about.

 

Hopefully one of our tech members will jump in with some insight into your radiator fan issue.

 

Good luck with whatever you decide to do.

Thanks! Mostley to get better gas mileage and save where on the compressor, when it come springtime that's when I found out needs the compressor to dehumidify the windows a fair amount of previous cars I owned had bad AC systems and ended up just being pure heat during the winter. Right now I have the fuse pulled because I'm assuming at 32 the compressor supposed to not engage as I know below a certain temperature It could damage it, I have a feeling the fan and compressor would engage no matter what the air temperature sensor is reading whether it be 30 or -1. Don't want to damage the AC system to get this fixed. It's an odd situation it's fan off, unless you turn it on defrost, with the fuse pulled did not think it would call for fan and did not before untell today, but it may so that's not the unusual part. Engine can be ice cold take it out of defrost/AC even turning HVAC completely off the fan still stays running on low speed. so trying to narrow it down if it's the fan controller mounted on the side of the fan shroud (hopefully) or worst-case a problem with the PCM of the car turning it on when it's unnecessary to do so. Only way I can get by with doing heat now without fan is keep HVAC off when I start the car let it get up to full operating temp, then turn it on windshield defrost,fan comes on and stays on no matter what setting you have it then after even if HVAC is off. Only time it resets per say is when you start the car and do not select any mode that would cause the AC to come on. This one's got me stumped somewhat? Think I'm going to have to take it to a mechanic with a high end scan tool to see if the PCM is calling for fan or not for the relay/controller on the fan is just sticking on. Neither the less waste of gas sitting at idle for 10 minutes to get up to operating temp then just start to turn on defrost and wait another 10 minutes to clear the windows. fan never turned on before and car never goes over 190 degrees, so probably could be "ok" during the winter time just unplugging the fan but I have a feeling it would throw a code and possibly the CEL because it could not communicate with the fan controller and in summertime would definitely possibly be needed and definitely for the AC. Definitely not a problem of not working a problem of working when it's supposed to "not"

[bbf2530]

9 hours ago, g3justin said:

Thanks! Mostley to get better gas mileage and save where on the compressor, when it come springtime that's when I found out needs the compressor to dehumidify the windows a fair amount of previous cars I owned had bad AC systems and ended up just being pure heat during the winter. Right now I have the fuse pulled because I'm assuming at 32 the compressor supposed to not engage as I know below a certain temperature It could damage it, I have a feeling the fan and compressor would engage no matter what the air temperature sensor is reading whether it be 30 or -1. Don't want to damage the AC system to get this fixed. It's an odd situation it's fan off, unless you turn it on defrost, with the fuse pulled did not think it would call for fan and did not before untell today, but it may so that's not the unusual part. Engine can be ice cold take it out of defrost/AC even turning HVAC completely off the fan still stays running on low speed. so trying to narrow it down if it's the fan controller mounted on the side of the fan shroud (hopefully) or worst-case a problem with the PCM of the car turning it on when it's unnecessary to do so. Only way I can get by with doing heat now without fan is keep HVAC off when I start the car let it get up to full operating temp, then turn it on windshield defrost,fan comes on and stays on no matter what setting you have it then after even if HVAC is off. Only time it resets per say is when you start the car and do not select any mode that would cause the AC to come on. This one's got me stumped somewhat? Think I'm going to have to take it to a mechanic with a high end scan tool to see if the PCM is calling for fan or not for the relay/controller on the fan is just sticking on. Neither the less waste of gas sitting at idle for 10 minutes to get up to operating temp then just start to turn on defrost and wait another 10 minutes to clear the windows. fan never turned on before and car never goes over 190 degrees, so probably could be "ok" during the winter time just unplugging the fan but I have a feeling it would throw a code and possibly the CEL because it could not communicate with the fan controller and in summertime would definitely possibly be needed and definitely for the AC. Definitely not a problem of not working a problem of working when it's supposed to "not"

 

Hi justin. Just some more to think about: You will do more possible damage to the AC compressor by disabling it than the wear and tear you think you are avoiding, or gas you think you are saving. The simple explanation why? Even if not being used, the AC compressor needs to run once in a while to "exercise" the system, keep the seals properly lubricated, etc.

Even if not needed for AUTO/AC/Front Defrost duty, it is best to run the HVAC system on AUTO/AC or Front Defroster at least once a month or so. Again, to keep things freely moving and lubricated.

 

As far as saving fuel: The AC compressor does not run or use fuel unless you use the AUTO/AC/Front Defroster settings. So instead of disabling the AC compressor, just do not use those settings unless you need to. Especially since disabling it does not seem to have helped with the fan problem (if I am understanding your post correctly).

 

Also, the AC compressor is most needed in the winter (or even summer), when the windows are usually closed during driving because you need heating or cooling. It is needed for de-humidification in the winter and de-humidification/cooling in the summer.

It is humidity and temperature differential between the interior and exterior of the vehicle that causes fogging. And it is winter and summer (especially winter) when there is the widest temperature differential between the interior and exterior of the car. In the spring and fall, the temperature differentials between the interior and exterior are minimal. So in spring/fall you can usually use the vent settings. Or you can comfortably crack a window or two if necessary. Or even drive with the windows wide open if you feel like it. But in the Northeast, we often can't comfortably do that in the winter and summer.

 

Bottom line is you need the defroster most often in the winter. And running it at least once a month or so is the best way to keep it healthy. Disabling it is not.

 

Also, if you could do a favor for those trying to help you? Posts can be difficult to read with no paragraph breaks, especially when they are longer. While it is easy for you to read and understand what you wrote  (because you wrote it), it can be difficult for others (well, definitely me) to read and fully comprehend a long, solid block of word. Even after reading your previous post several times, there are still a few items where I am not exactly sure what you are saying.

 

Anyway, while I do not think my information about the AC compressor will necessarily change your mind, it is still information you should be aware of.

 

Have that fan checked, keep us updated and good luck.

Edited February 26, 2020 by bbf2530