blue00r6

Now I'm not sure how the HVAC system is set up in these cars, but on the passenger side of mine, when i turn up the fan to past 3 bars, there is a squeaky rotational sound - sort of like a hamster running really fast on a rusty wheel.

It comes and goes, happens more on very cold mornings (30's) and seems to be encouraged when hitting sudden jolts in the road.

Anyone had an issue with this? Is there a TSB or a quick known dealer fix?

Ted in Toronto

Mine did the same thing after 2 years. The first winter I had the car the fan froze up solid due to wet snow, they repaired that problem with a deflector of some sort but then the next winter I got the noisy fan. They then replaced the fan motor under warranty.

Blazeitup123

I think its normal. My glk and c class both do this.

Chi-Benz

Same thing here for me. Just started happening this winter (55,000 miles). Coming from the passenger side as far as I can tell. Quite annoying. Any DIY fix or suggestions on how to fix (other than going to the dealer)?

Glyn M Ruck

It's a common problem on Mercs. Pull the blower & lubricate the squirrel cage bearing with thin grease - or replace.

blue00r6

Where is the blower located? it sounds like the noise is coming from right behind the passenger side vent..

Blazeitup123

pop the hood, is the big plastic housing top left.

w204tr

The same started to happen to me last week. However, mine only does that when I push the button for the indoor air circulation. Would that be the same issue? By the way, it disappeared by itself at the moment.

Jason B

I have a slight flutter sound when at 4-5 bars. Not bad, and didn't know if this was normal. Kinda like an electronic sound too a little.

BenzTWM

I have the same issue. It is accentuated when I have my heat/fan up high, and when hitting hard bumps or turning sharp corners. The noise happens when idle and when driving, however it is accentuated when I hit the pedal.

Any tips on how to DIY fix? I'll try greasing/fidgeting with the blower this afternoon, but anything else would be appreciated!!

Thanks.

Cleanbenz

Mine just started the fluttering. It's annoying as hell

earlybird

A couple of weeks ago, my blower motor was replaced under the extended warranty. The squeaky noise is gone.