A/C stops blowing any air all of a sudden, while still staying "On"
Thread Starter
Out Of Control!!
Joined: Jun 2008
Posts: 10,557
Likes: 24
From: Earth
Porsche Macan S SportDesign / Ex M-B's: 11 & 10 & 06 E350's, 02 S500
A/C stops blowing any air all of a sudden, while still staying "On"
Anyone know what this could be. It's been occurring for a while now, but lately happens more frequently.
I'll have the A/C on, and all of a sudden, while the power is still on, no air at all is being blown out of the vents. I'll have to turn it off and on several times, which usually still won't work, then start playing with all the buttons, and eventually it'll work again.
I'll have the A/C on, and all of a sudden, while the power is still on, no air at all is being blown out of the vents. I'll have to turn it off and on several times, which usually still won't work, then start playing with all the buttons, and eventually it'll work again.
MBWorld Fanatic!
Joined: Dec 2006
Posts: 6,498
Likes: 335
From: Europe
223.168 & 213.012 & 906.633 & 214.005
On other models it is usually the regulator that fails. The symptoms can vary from the fan stopping intermittently to the fan blowing at full speed. Are you sure they replaced the motor and not the regulator or perhaps they changed both (the regulator is attached to the motor).
Newbie
Joined: Jun 2009
Posts: 8
Likes: 0
2006 E350
Anyone know what this could be. It's been occurring for a while now, but lately happens more frequently.
I'll have the A/C on, and all of a sudden, while the power is still on, no air at all is being blown out of the vents. I'll have to turn it off and on several times, which usually still won't work, then start playing with all the buttons, and eventually it'll work again.
I'll have the A/C on, and all of a sudden, while the power is still on, no air at all is being blown out of the vents. I'll have to turn it off and on several times, which usually still won't work, then start playing with all the buttons, and eventually it'll work again.
My dealer looked up the service advisory and installed the missing humidity sensor at no charge. Problem solved.
MBWorld Fanatic!
Joined: Mar 2004
Posts: 5,017
Likes: 16
From: Ft. Lauderdale Area, USA
2015 ML 350
Its a bad blower fan control module located somewhere under the dash on the right side of the car. Mine had to be replaced twice to get a good one (on my '04). What triggers it usually is when the blower fan enters the highest fan speed aurtomatically, or you press Hi or Max or go into defrost mode. Its almost like the fan draws too much current & then trips off line untill it resets. All the lights & indicators say that the system is working except... no fan. Its random & an intolerable condition. It is a well known problem with a well known fix.
Thread Starter
Out Of Control!!
Joined: Jun 2008
Posts: 10,557
Likes: 24
From: Earth
Porsche Macan S SportDesign / Ex M-B's: 11 & 10 & 06 E350's, 02 S500
Yup, that's the one. Is it an extensive fix? I.e do they have to remove the dash or any of that stuff? Fortunately I have a Warranty.
MBWorld Fanatic!
Joined: Mar 2004
Posts: 5,017
Likes: 16
From: Ft. Lauderdale Area, USA
2015 ML 350
No major dismantling... all from under the dash if you're worried about them "tearing apart" your car. It was returned to me as an undetectable repair... except that I never had the problem again after the 2nd replacement. 
Last edited by Barry45RPM; Aug 26, 2009 at 03:03 PM.
Trending Topics
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Thread Starter
Out Of Control!!
Joined: Jun 2008
Posts: 10,557
Likes: 24
From: Earth
Porsche Macan S SportDesign / Ex M-B's: 11 & 10 & 06 E350's, 02 S500
Cool thanks. Yeah I was hoping they wouldn't have to tear the car apart or anything 
The problem now is, getting them to "witness" it, as it's completely random in when it decides to act up.
The problem now is, getting them to "witness" it, as it's completely random in when it decides to act up.
Out Of Control!!
Joined: Jul 2003
Posts: 15,901
Likes: 4,632
From: North Scottsdale, AZ
'71 Pinto
Senior Member
Joined: Nov 2008
Posts: 253
Likes: 0
From: DC Metro
W210 E55, W211 E3504M, E90 325i
Its a bad blower fan control module located somewhere under the dash on the right side of the car. Mine had to be replaced twice to get a good one (on my '04). What triggers it usually is when the blower fan enters the highest fan speed aurtomatically, or you press Hi or Max or go into defrost mode. Its almost like the fan draws too much current & then trips off line untill it resets. All the lights & indicators say that the system is working except... no fan. Its random & an intolerable condition. It is a well known problem with a well known fix.
MBWorld Fanatic!
Joined: Mar 2004
Posts: 5,017
Likes: 16
From: Ft. Lauderdale Area, USA
2015 ML 350
As I said... well known problem with a well known fix. I wouldn't monitor anything... they know about it, plus there's a DTB. Make an appointment, get it fixed. You get stuck on a hot day on the road & you will not be a happy boy... and if you are unlucky enough to have someone else in the car with you, all you'll hear is that you "should have bought a Lexus". (Can't believe it happened on an '07 though).
Member
Joined: May 2010
Posts: 97
Likes: 1
'06 E320 CDI, '04 Sprinter 316 CDI
Hi konigster,
Can you by chance tell me if this DTB P-B-83.25/76c would still work with the dealer on a 2006 E320 CDI? Is there a way to diagnose this for sure as the dealer is rather far from where I live? Meaning the humidity sensor.
I had the symptom arise for the first time this past weekend.
Hot day, long 9 hour drive, and after 6-7 hours or so into the drive, air ceases to blow in the normal velocity even though it sounds like the blower is turning. The A/C air is blowing like there is no fan turned on, so basically hardly any air coming out of the vents.
If I put it on defrost, still no air, or next to no air should I say.
I remember reading something a few years ago about some HVAC valve that is under the windshield driver side that fails if my memory serves me well. This is what is feels like, the fan blower motor seems to be making a noise, yet no air comes out almost like the duct is blocked, but once again, this is just my theory.
Any assistance would be greatly appreciated to lead me in the right way. I am good with electrical troubleshooting especially if I know what to look for.
Many Thanks in advance.
Out Of Control!!
Joined: Jul 2003
Posts: 15,901
Likes: 4,632
From: North Scottsdale, AZ
'71 Pinto
Your VIN is not included in DTB. Check both blower (current part # 2118300908) & blower regulator (current 2308216451).
http://workshop-manuals.com/mercedes...ns/page_15906/
https://www.google.com/url?sa=t&rct=...,d.cGU&cad=rja
http://workshop-manuals.com/mercedes...ns/page_15906/
https://www.google.com/url?sa=t&rct=...,d.cGU&cad=rja
Member
Joined: May 2010
Posts: 97
Likes: 1
'06 E320 CDI, '04 Sprinter 316 CDI
Your VIN is not included in DTB. Check both blower (current part # 2118300908) & blower regulator (current 2308216451).
http://workshop-manuals.com/mercedes...ns/page_15906/
https://www.google.com/url?sa=t&rct=...,d.cGU&cad=rja
http://workshop-manuals.com/mercedes...ns/page_15906/
https://www.google.com/url?sa=t&rct=...,d.cGU&cad=rja
The more I read, the more I know the evap tube must have frozen and that caused the problem. I drove 700 miles straight, it happened after 3/4 of the drive was done, weather hot humid, all during the day. I parked it for 90 minutes then drove it for 15 minutes before calling it a day, and it was back to acting normal, like the evap freezing had thawed. Once again, I did not get a visual, but it seems like this will be a rare occurrence if this long drive is a requirement to reproduce the symptom, time will tell.
I guess I should invest in both the motor and regulator as they are a known problem and its just a matter of time.
Newbie
Joined: Oct 2018
Posts: 1
Likes: 0
E280 2005
Thank you for the links konigstiger,
The more I read, the more I know the evap tube must have frozen and that caused the problem. I drove 700 miles straight, it happened after 3/4 of the drive was done, weather hot humid, all during the day. I parked it for 90 minutes then drove it for 15 minutes before calling it a day, and it was back to acting normal, like the evap freezing had thawed. Once again, I did not get a visual, but it seems like this will be a rare occurrence if this long drive is a requirement to reproduce the symptom, time will tell.
I guess I should invest in both the motor and regulator as they are a known problem and its just a matter of time.
The more I read, the more I know the evap tube must have frozen and that caused the problem. I drove 700 miles straight, it happened after 3/4 of the drive was done, weather hot humid, all during the day. I parked it for 90 minutes then drove it for 15 minutes before calling it a day, and it was back to acting normal, like the evap freezing had thawed. Once again, I did not get a visual, but it seems like this will be a rare occurrence if this long drive is a requirement to reproduce the symptom, time will tell.
I guess I should invest in both the motor and regulator as they are a known problem and its just a matter of time.
Member
Joined: Oct 2017
Posts: 86
Likes: 11
From: Charlottesville, Virginia, USA.
2004 W211 E320 Sport
My 04 E320 has a similar problem. A/C fan works for a short while when outside temps are high and hot, then reduces fan speed to level 3 and won't go higher for some time. Not sure if related, but the cigar lighter in the console (2 of them) also goes dead when the A/C motor thing occurs (thus can't charge iPhone). Strangely, the A/C fan may (or may not) resume normally at any time, usually after a stop/start at a traffic light, etc.
Very strange, annoying and hot when temps around here in VA rise into the 90s.
Ideas?
Very strange, annoying and hot when temps around here in VA rise into the 90s.
Ideas?
Member
Joined: Oct 2019
Posts: 138
Likes: 15
04 E55 AMG
My 04 E55 did this a few months ago in Arizona when temps were over 100.
I drove it around for a few minutes and thankfully it started working again.
Anyway, FCP sells the part for $117: https://www.fcpeuro.com/products/mer...tor-2308216451
I drove it around for a few minutes and thankfully it started working again.
Anyway, FCP sells the part for $117: https://www.fcpeuro.com/products/mer...tor-2308216451
