Air Cond. Issues
 

Ok the question:

I have a 2001 E53 with 125K on the clock. Naturally now that the weather is very hot some HVAC issues have come up. The air gets warm when stopping at idle. Gets cold again at road speed? System has never needed service. Should the auxilary fan come on every time the system is turned on? Weasel please weigh in on this one. Was always ice cold until recently.

Follow Up
 

Well its the auxilary fan. Is it worth diagnosing the fan. or just replace? Also I can find a bumper removal DIY. Anyone know of one?

In my case the freon was low... I just had it recharge and it all good again..

I had the same thing - the auxiliary fan had failed. The dealer assured me that it either worked or it didn't - no need to do a diagnosis. He also said this was a fairly common ocurrence on the e53's. I just had it replaced and it's working fine now.

If you hit "max" ac button the Aux Fan should turn on. If it does not check the wire connectors next to fan on the passeger side (should be easy to see/find). If the connecters are good then you probably have a faulty Aux fan.
Dealer replaces it for $550 (new fan) plus 4 hours labor and they will slap on
$200 for a freon evac and recharge.
A recent thread talks about the best price for Aux fan online. low $300s i think.
If you are handy, try replacing it yourself, and save about $1000.
When replacing by the "book", the front bumper needs to be removed completely. But my indy said that there is a way to do it by just loosening the bumper. the old fan slides out and is replaced in much less time/labor. (I don't know the details, maybe somebody else could chime in... )

I would guess that the freon level is not low since the ac cools as the car gains speed. (wind entering the kidney grills does the job of the aux fan). So if you do go to a dealer tell them to not perform the freon recharge (unless the fan can't be replaced without evacuating the freon. I'm not sure)

Good luck,
Rui

Check the "How To's" and "Articles" links at the top of the page. There are DIY instructions on this topic.

Good luck!

I just replaced my aux. fan about a month ago and on a 06' there is no way to get it out without taking the front bumper cover completly off. I tried with it just loose, not happining. Unless you really press and pull on it and the fan in opposite directions. To me it was just as much work to completly remove it, then to chance scratching the bumper cover. BTW- I got my fan @ the dealer for just over $400. I'd say the avg. home mechanic could do it, beginner = fail. I used to be a Toyota mechanic, so I have the exp. and the proper tools. Took me about 3 hours start to finish.