Climate Control Fan not working properly '98 E320
 

1998 E320 W210
129,000 miles and in impeccable condition...except:

My A/C - Heater fan seems to be malfunctioning.

When I turn on my fan beyond the 2nd mark when pressing the "+" button, the fan does not increase in velocity. I also hear a VERY slight high pitch sound when I increase the fan speed above the 2nd mark. Everything else seems to work fine; blows cold and heater works.

Any ideas on the problem and what it might entail to have fixed??

Thanks!

Your blower motor regulator has burned out. It is located underneath the dash on the passenger side. Mercedes revised the blower motor and regulator in the middle of the W210 production. The old regulator (that you have) is no longer available; you must buy the revised motor and regulator together. The parts cost about $800. If you take it to a dealer, they'll probably charge you $1k to fix it.

BUT...

The blower regulator from the W140 S-class is compatible with the early-style W210 fan motors. You have to splice your old wiring harness onto the new regulator, but other than that it's a direct fit. Replacement takes about an hour of your time and I believe costs between $100-$200.

I'll find forum threads for you that discuss how to do this.

It seems the part number you need is 140-821-83-51. There are two sources for the part, one from France and one from Germany. Consensus is that the German part is higher quality.

Here are links to other threads with further explanation. It wouldn't hurt for you to search the archives...

MBWorld

• 96 E320: a/c only blows on the low setting. Any ideas?
• 98 E320 Blower fan - working on low
• Fan Regulator (AC fan not fully functional)
• AC help (flap test failed)

BenzWorld

• Changing blower motor Regulator - HELP!
• AC Problem - Low Flow in Center Vents / Minimal Flow in Rear
• A/C - Heater Problem

Lexrex,

You're a Gem! Thanks so much for giving me this information. I will study the archives and see what I find and report back so others with the same problem can see what I had done. Thanks again!

I love this forum and those that take the time to respond. Wonderful!

Johnny

No problem. Hey, if you have a digital camera, it would be great if you could take pictures as you do the procedure and post a pictorial how-to guide.

This is a very common problem, and I'm sure a lot of people have wasted a lot of money fixing it the $tealer way.

Pls do
 

Yes pls do make a how to..

For some of the money you save u can even buy a camera if u dont have one.
(unless of cause u have the new style blower)
/kim

Just so happens I'm a photographer. I'll post a How To.

My Photo Page

And a skilled one too... :-)
Nice pictures u have there ...
/kim

Just had this repair done...
 

it was about $400.00 and they used the "S" class regulator...working great now...I have a '97 E420.

Hi there,

I was hoping someone might be able to help me. I have a 96 E320 with a shot blower motor regulator. I bought the S-class replacement, and soldered the old wire harness onto the new regulator. Only problem is, as soon as I plug it in, the blower motor starts up full blast, even though the car isn't even turned on.

I'll admit, I'm a novice here, but I believe I soldered the old wire harness on correctly. Any idea what I might be doing wrong?

Lastly, when I turn the car on, trying to adjust the thermostat doesn't do anything to turn down the air down from full blast. Is it possible I have my wires on incorrectly/backwards to make the blower motor run at full blast upon plug in?

I'm attaching a picture of the finished solder job in hopes that someone might be able to help me. It would be greatly appreciated!