I have a 2011 E350 Bluetec. I took it in for service because, when the interior was hot, the a/c would come on full-force, then instantly die down to almost nothing. Even trying to over-ride this via the manual fan switch would only give a second or two of relief.

I took it in and they tried everything, down to replacing the fan itself. Nothing worked. Then they said there was some new 2011 part called something like a battery voltage regulator (sorry - I was so mad I didn't take notes and I haven't picked up the car yet) that would have to be replaced. A week later, that is replaced and I get the dreaded phone call today - "Uh, that's the way the engineers say it's supposed to be to save fuel."

Really??? Can anyone give me any insight here? This cannot be how a $60,000 vehicle is supposed to behave in the summer. It can't be.

2011 BlueTec. Nearly identical! AC will start full force, then close to minimal for around 5 sec then resume with a normal air flow that cools quickly. It usually happens after the first start of the day. Also, it happens if the car if left for several hours. Only once has it not happened, that was a surprise. Please post a reply if yours was fixed. My service is not due until around 2 months. Other repairs. If the ambient temp is over 86, with the AC on, the idle is 200 rpm above normal. Turn off the AC and the idle is normal. I believe this is a software fix. One other problem, the gas cap door retention no longer works.

I've seen this on the BlueTEC as well - really annoying! The A/C cycles on and off at full fan speed as you're driving as well.

You could try asking the dealer to reprogram your HVAC unit to the same spec as the standard E 350 (gas). There are control codes stored within the HVAC unit that can be modified, I'm just not sure if the dealer would be willing to try altering the coding not knowing what the long term implications might be.

Mine does the same thing. I was told by my service department that this is how all of them are. It does in fact cool very quickly despite the wierd variations in fan speed. I would be interested if any finds any new information.

Wait - ImInPA - didn't you kill a cow for your steering wheel?

The idle increase (ambient over 86) when the A/C is on also occurs on my 2011 E550. Switching the system off totally and then on returns the idle to normal. However, the increased idle will come back within 5 min. Dealer has loaded the latest software with no change.

mine does the same thing.. truely annoying.. going in for 10000 mile service on 7/11/2011 and I will tell service manager...will update asap

Don't be a kill joy...lol. The amount of leather on the steering wheel would not require the killing of anything. There are women out there that have had more skin removed from their chins, than what is on my steering wheel.

Haven't noticed this problem.However,I always use the manual settings for the A/C (temp,fan speed),never the automatic setting.

+1

Anything new on this issue?
Sucks having $60,000 car with AC that craps out in 115 degree heat.
No one at MB can give an honest answer.

Last June I took my Bluetec out to Denver via I-70.Experienced 105 degrees for two straight afternoons in full comfort.But as I said earlier I never use the automatic setting.Perhaps that's why I don't have this problem.

It only happens for the first 5 - 10 minutes.
Blower goes off and on

Mine does this too.

When it's really hot in the car, the AC comes on full force, and then the blower shuts down for a few seconds, and then it comes back on. I had thought at first that it had to do with low fan power at idle, but discovered it does it even when the engine is revving.

The dealer looked at it at the 30K service, replaced something, and it still does it.

I am actually glad to know I am not the only one, sounds like it is something software rather than hardware.

I won't sweat it anymore.

Has anyone resolved this issue. I live in Texas and the summers are always hot. I didn't experience this problem until the second summer. It also occurs on the heat setting, no air on, and on manual and auto. Very inconvenient since I use air almost all year. The dealer has replaced fan motor twice and reprogramed the software several times. Mercedes says they are working on a solution but as of 2014 no solution.

Sorry to bring up the old thread.
Noticed this happened to me yesterday when outside temp is hot. Set my climate control to any setting with temp at Lo or 60, but the fan just failed to blow any air. This morning the fan worked fine when the temp outside was around 38.

MB vehicles have had ac problems since forever. I think they have given up on trying to fix them.

thats a relief thanks lol
people with AC problem will like this haha

any one did find the issue ? i have the same issue with the heater ...the fan runs full force on the acc position but when starting the car goes to minimum speed ......i dont know if related but heat set...heated steering and some times other thing in the car stop working in the car....even had the red batt screen
goes off after and runs good
have a new alternator and the battery is good so...