Seat Cooler Noise

[18MaxPlat]

I have a 2018 Expedition Max Platinum with less than 700 miles on it. There has been an annoying low-volume electronic noise since day one. The noise sounds similar to a bad fluorescent light ballast, buzzing at a fairly low frequency range, then randomly jumping to slightly higher frequency for fractions of a second. I downloaded a tone generator app to my phone try to match the frequency, but I can't really duplicate it with a single frequency (to be expected). It seems closest to the 300-400 Hz range, but varies. Once I notice this sound, I can't ignore it.

I took it to the selling dealer last Thursday, and they had a guy ride around with me to listen for the sound. He acknowledged hearing it, and that it was an unusual sound, but was otherwise noncommittal. After the service tech (different person) checked it out, they insisted it is normal engine cooling fan noise. I disagreed, but couldn't prove differently at the time.

The next day, I accidentally discovered that the noise goes away when I turn off the driver's seat cooler. I had set it on the high setting when I first got into the vehicle, and had left it there, but turned it down a notch that day and immediately noticed the difference. I don't hear it at all with only the passenger seat cooler on, and it drops in volume as I lower the fan speed on the driver's seat cooler. That seems to suggest that it's speed-related fan noise, but I can hear the separate sound of the fans. This is different than any fan noise I've recognized.

In the service manual I only see a control module and the 2 fans (seat base fan and seat back fan) in the system. I see no indication of a separate inverter or other electronic device that might be making this noise.

Has anyone else had this problem? Any solution?

 

[aggiegrad05]

When my driver's seat cooler is all the way on high, I definitely hear a loud fan noise (it's an electronic hum, not an air woosh). If I turn the cooler down to medium or low, it goes away. And yes, there is always an air flow noise from my back when it's on high, but this is separate and sounds like it's coming from under the seat...so I guess that is the butt fan.

 

[rcompart]

Same thing here and yes, only the driver seat and only when on high. Forgot to bring it up last time I was at the dealer but will try to remember the next time I go in.

 

[edizzle]

You know, it is not silent right? It is a traditional AC system that blows air through the perforated seats. So just like you can hear the AC, you will hear the cooled seats

 

[aggiegrad05]

You know, it is not silent right? It is a traditional AC system that blows air through the perforated seats. So just like you can hear the AC, you will hear the cooled seats

Yep. Never thought to raise the issue with the dealer. That’s the difference between a ventilated seat and a cooled seat...these puppies are actively blowing cold air at your nethers...if I DIDNT hear some air noise I’d think they were broken.

 

[18MaxPlat]

Yes, I realize there is normal audible fan noise from these seat cooling systems. I had the same type of system in a Yukon XL, and my Dad has it in his Suburban. You can hear the fan noise, especially when on the high setting, but I've never found it to be objectionable, and the normal fan noise isn't objectionable in this Expedition, either. It's the abnormal sound that's so annoying. That's why my original post stated " I can hear the separate sound of the fans. This is different than any fan noise I've recognized". and "The noise sounds similar to a bad fluorescent light ballast, buzzing at a fairly low frequency range, then randomly jumping to slightly higher frequency for fractions of a second". This noise might be a bad fan or fan bearing, or some controller noise; I don't know. But it's definitely not a noise that any normally functioning fan should make. And it's certainly not something a manufacturer should consider acceptable in a vehicle of this class. I expect that it will be resolved by the dealer under warranty, eventually, but I wanted to find out if others were experiencing the same thing, and may have found a solution.

 

[dlcorbett]

Maybe its your speakers, some interference causing them to blank out. I would imagine since your truck has noise cancellation, theres always a tone present from yoyr speaker. Could be a electronic malfunction.

 

[Dormammu]

When my driver's seat cooler is all the way on high, I definitely hear a loud fan noise (it's an electronic hum, not an air woosh). If I turn the cooler down to medium or low, it goes away. And yes, there is always an air flow noise from my back when it's on high, but this is separate and sounds like it's coming from under the seat...so I guess that is the butt fan.

This for me too.

On day one of ownership I was thinking..."this is going to drive me nuts!"

Now I never even hear it.

 

[Donna Timmons]

It is definitely the fans in the seat heater. It was driving us crazy too until we realized what it was. Our max plat has less than 5k . Same issue. Enjoy the car we love ours!

 

[willy saucerman]

Wow, first 5 minutes on site and first question answered. Thanks guys