Hi to the W211 forum! I just bought a 2003 E500, black/stone, to replace my 97 E420. The W211 is an amazing car! I have an odd intermittent "chirping" sound that only occurs when the a/c fan is set to level 2 or higher. I assumed it was the fan bearings, but the squeaking only occurs when the steering wheel is turned to the left. The squeak dissapears instantly if the wheel is at dead center or turned to the right. Also, any acceleration, however gentle, causes the squeak to dissapear instantly, regardless of steering wheel position. Does someone know the fix for this?

 

There have been similar reports. The fans are pretty short lived. When you turn the wheel at low speed, the motor rpm drops slightly and the squeak appears. Accelerating picks up the alternator voltage, raises the fan speed, squeak disappears. They are about $130 at aftermarket houses. Made by Behr and match the OEM (including same crappy bearings). Takes about 1 to 1-1/2 hours to replace. Many posts here about the problem. Do a search for pics etc. Mine would only squeak intermittently on lowest speed. If it is the fan, it will get progressively worse. One member cleaned his with breakfree or compressed air or something. He said it quit. The fan bearings disintegrate (graphite? ) and pollute the whole assembly. They are quite difficult (impossible?) to disassemble. Good Luck

 

Mine does it when I accelerate. I think the vibration from the engine has to do with it. I just live with the chirping sound until the fan dies. I mean taking out a working fan and putting a new fan which eventually will be noisy isn't that ideal to me. I see MB EPC has a newer part # for the fan. It is hard to say if it fixes the crappy bearing problem. OEM ones are not cheap neither.

 

Thanks guys. I found the write-up for the blower motor removal. I'm going to try cleaning things up and a little molybdenum lubricant instead of replacing the motor. I'll post my results.

 

Can you post the link ?

 

https://mbworld.org/forums/3888972-post13.html

 

Removed the blower fan tonight and lubricated the motor bearings with some synthetic oil. The squeaking is gone, and the fan is noise-free on all settings. This may be a temporary fix, but at the very least I've learned that it only takes about 30 minutes to remove and replace the blower fan. I'm really impressed with the engineering in the W211 so far; it seems that they really gave some serious thought to ease of serviceability of common wear components. If you've ever replaced a blower fan in a W210 or R129, then you would really appreciate this design.

 

Replace the motor vs lube.

"good judgment comes from bad experience"

 

I have a 2004 CLK 200. The C209 is a fantastic. I also had a squeaking air con. When I ran the fan with the air con turned off, the squeaking went away, but came back again as soon as I tried to activate the air con, at slow and faster speed settings. The air con didn't cool down the air either so I knew the air con gas needed refilling.
I thought i would fix the squeak first. I thought it was the fan at first, and replaced that with no luck. I then read about the symptoms and decided I will try changing the serpentine poly v belt. While waiting for the part to arrive, with the current heatwave in the uk, the heat was unbearable so I thought I would go ahead and refill the air con gas and live with the squeak for a few days. I am surprised and pleased to say that the simple act of using a air con leak cannister, then the air con gas refill not only got the cold air working, but it also fixed the squeaking coming from the air con.