2002 X5 3.0 fan weirdness ... does this sound like the FSR?

[Bottomfeeder]

Hey Everyone -

Recently I've been having some intermittent weirdness with the blower while running the AC. Occasionally it will just stop blowing cold air, and not respond to increasing the speed on the AC control unit on the dash.

It has only happened a handful of times, but so far returns to working normally after either (1) restarting the car, (2) turning the AC on and off a time or two, or (3) doing nothing until it just randomly starts working again.

From what I've read, this kind of erraticness is pretty classic final stage resistor behavior. Does that sound right? Anything else I need to be considering as a potential source of this?

And lastly, is the FSR a part that it's best to go with BMW OE, or are other options reliable? There are some super inexpensive ones out there.

Thanks in advance for the advice!

Chris
Lockhart TX
2002 X5 3.0 Titan-silber
2005 X5 3.0 Schwarz-2

[andrewwynn]

I’ve had success with knock off FSU.

I’ve had problems with the auto sensor and fan speed.

Set to auto then hit max and turn off max. That would fix without restarting the car. (On wife’s she didn’t have max but “rest” and if I turned the temp to min. or max. that also would work.

The symptom was the fan speed would drop even before the temp was reached hot or cold. This weird kick in the butt made it work again.


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[X5chemist]

I've been running an aftermarket FSR too. Two years or so. All good. Hopefully, it's not the blower motor fan! When resistors fail, usually a speed setting fails. Starting and running at the same fan speeds points to blower motor resistance start.

[Bottomfeeder]

Thanks for the good counsel, gentlemen ... think I'll try an aftermarket FSR and see if that makes the problem disappear.

Originally Posted by X5chemist

Hopefully, it's not the blower motor fan! When resistors fail, usually a speed setting fails.

Oof ... yes, I sincerely hope it's not that, too. That might break my spirit. :-)

Chris

[andrewwynn]

Originally Posted by X5chemist

I've been running an aftermarket FSR too. Two years or so. All good. Hopefully, it's not the blower motor fan! When resistors fail, usually a speed setting fails. Starting and running at the same fan speeds points to blower motor resistance start.

No resistors on x5. FSU does all the speed control.

You can jumper the pins on the FSU connector to confirm the blower motor is ok.

[Bottomfeeder]

Just wanted to check in with an update as I'm sure everyone is on the edge of their seats with anticipation wondering about my AC issues. ;-) However, it's already starting to get hot here in central Texas (we don't really do Spring so much) and last week my workarounds stopped working-around and nothing I did would get the fan blower to work.

Installed a replacement FSU this afternoon (went with the Mahle/Behr part and bought an extra to have on hand) and I'm back in business. Breathing a sigh of relief that it wasn't the blower motor itself. The unit I pulled was clean as a whistle, but the date on it was 12/02 so guess I can't complain too much.

Thanks all -

Chris
Lockhart TX
2002 X5 3.0 Titan-silber (40K)
2005 X5 3.0 Schwarz-2 (85K)

[andrewwynn]

Golden oldie! Fat pins. The new models have twice the pins that are cylinders not cones. Pretty amazing itt lasted that long!

[X5chemist]

Sweet! Replace the dryer and add some R134! Mine cools to 42F on a hot day! Austin traffic is no joke. Tinted glass helps a lot too.

[haigha]

Glad you got it fixed, @Bottomfeeder.

I went through two FSRs in the first three years of ownership... now 18+ years later, still on the third one, which was an eBay knockoff, IIRC. I think it was the 10+ hour road trips I did during that period that caused the failures.

I put AC Pro High Mileage in two years ago and haven't had to recharge it yet. Before that I was using their regular product and doing a recharge every spring for about the previous three years.

https://www.walmart.com/ip/A-C-Pro-H...12oz/444741999

https://www.amazon.com/Pro-ACP307CA-.../dp/B07RMSDWJ5

Also has UV dye, in case you need to track down a leak.

[andrewwynn]

or confirm that the leak was external such as elbow joint, which in my case it was