I’m confused about the A/C. For some reason when I have the “AC/OFF” button on. The A/C seems to still turn on when I start the engine.. Then after about 5-10min after start the A/C finally shuts off. Is this normal?? Shouldn’t the A/C be off constantly with the AC off button?? Or is this just the characteristics of the e-class climate control.. Any input is appreciated.

 

If you have 4-zone AC, check to see if the key dependent feature is on. You can turn this feature on/off via the instrument controls. In addition this feature can be set to activate the charcoal filter, automatic mode, manual mode, or selected temperature target value upon starting the engine.

 

I have the standard 2 zone system in my W211 and it works the way you described. I remember seeing a post about this a couple of years ago that explained why it works that way.

 

Correct me if I'm wrong, but... The AC Off button doesn't shut down the entire climate control system. What it does is: not permit the A/C compressor from operating when the climate control system is running. The system probably turns on & tries to cool, but when it realizes that the compressor is "out of the loop" and the system will never satisfy the thermostat setting, it goes into a very low fan speed instead.

The black button button labeled "o" in the center of the black button array shuts the ENTIRE climate control system down. Try that button if you dont want any fan activity when you start the car.

 

Good call. Mistook the AC/off for O button.

 

The "O" button does turn off the entire climate system..however I'm confused to the fact that when I have the A/C off (on) The A/C is stilll on when I start the car and then shuts off in about 5-10 mins after driving. On my old 01'clk there was a EC which kept the A/C off and it never turned on unless I pressed it off.

I'm just new to this climate control and hope this is a normal thing. anymore input is appreaciated..

 

Barry, did you get chance to see if your navigation DVD is MB part Q6460216?

 

Car back at the shop. Heat coming out of the rear A/C vents again. I put a call in to NJ to see if there is any fix for this. I'll have the car tonight & will check the p/n & post. (Remember that the disk in the unit now is NOT the one that caused the Audio system crash last time. The one in now came from the parts dept in a wrapped DVD case when the newest Navi DVD drive was installed.)

 

OK here you go:

(1) The A/C does have a humidity sensor and will activate the compressor if it's too humid out which activates it at morning and other start-ups even with the A/C off button set prior to starting.

(2) The switch actually puts the system into "SLEEP" mode. The system will continue running the compressor and will gradually shut down for about 10 minutes before it shuts down starting the car with the AC/OFF allowing for a more comfortable transition.

 

Thanks Konigstiger! **is this info in the manual??

 

No.

 

Resurrection of an old thread...

I have an 07 E350 with dual zone climate control. It too starts the A/C compressor every time I start car regardless of the A/C button. It has been Santa Ana weather here (ie: like 5% humidity) and the sucker still runs every time I start the car regardless of outside temp. Has the operation been changed in the later models? If not, should I bring it in?

 

Two zone climate system (code 580) the humidity sensor was deleted as of 7/05 production.

If within VIN range A845370 to B100720 and X189946 to X223159 one can mention DTB P-B-83.00/102 MAY07, claiming reduced air- flow/cooling after long drives dealer will install humidity sensor (part #2118300572) and evacuate/charge the system under warranty.

 

Thanks for the answer. So, are you are saying that the A/C will run for 10 minutes every time you start the car if you do not have the humidity sensor?

 

Hi all I looked every where but I cannot find an answer for similar issue. My question is if the AC off light is on that means AC is off, how would I recharge the AC if I have to have the AC running at maximum and the system is preventing the AC or compressor from running?

 

You missed the whole point completely off track. First if I'm going to spend $$$ then I will get the whole thing taking care and no need to ask questions here right? Right. Second the can is at minimum $30 where do you get it for $7.99? Now I am not trying to stat an argument here all I need is one straight answer what to do with the AC off light to recharge the system thank you.

 

1. Get the car hooked up to star and see what if any codes are thrown
2. Connect car to a good quality set of ac gauges and check readings.
3. If low evacuate system properly and pull vacuum on system and leave for awhile to check for leaks.
4. If no leaks found use proper filling techniques using weight to get system up to proper levels.

To do the job you need someone licensed to deal with the refrigerant as it is illegal to dump it into the air. But once system is evacuated you can do the rest yourself if you would like.

A straight up 12oz can of Freon is like $13 locally so IDK how you get $30+ unless you are talking about those crappy DIY kits which is not the way to solve ac issues as you can easily end up overfilling your system and causing expensive issues.

 

Thanks for the update. I started to do things myself about a year ago and I was hopping to do the job myself. After extensive research I learned there is no way for me to do it by myself so I got it serviced at a Mercedes shop. The car has been giving me a hint that I didn't pick up earlier like two days prior AC light on I was adjusting vents for my baby in the back when I felt cool air on one side and warm air on the other. I was also feeling not as cold as it used to be for a while so next time I will jump on it with the slightest change in the performance.