MBE550

I took the car to the dealer today for AC problem.
Two vents on the driver side front blowing kind of cool air but not cold.
The other 2 vents on the passenger side blowing cold air as it should.
I tried different temp settings but it didn't matter.
Anyone had this problem?

konigstiger

Most common cause low refrigerant

SZMB

Had this problem last year. Took it to an indy shop, they found the leak and replaced the O ring. $200 for parts, labor and charging up the system w/ freon.

MBE550

The dealer called me back yesterday telling me the probme is with a valve that directs the cold air to left/right, and will be covered under warranty.

Today, he called again saying that that wasn't the problem. It's low freon which could be due to a leak somewhere which they do not know yet.
He says if the leak is found it will be covered under warranty, but I have to pay for freon recharge fee of $250.

This is total BS. Shouldn't the recharge be covered under warranty if it's cuased by a defect? I don't know if freon should ever go low for 3 yr old car unless there is a leak.

konigstiger

Refrigerant system evacuate /charge should be included in repair process at no cost under warranty.

MBE550

Thanks for the info guys.
I got the car back just earlier.
They could not locate any leak, but did put dye in the system.
The AC works much better now, but still not as good as any cars I had in the past including 4 and 6 cylinder cars.
Even the loaner, 2008 C300 has much colder and stronger air.

Oh, and I did not pay for the recharging of AC.

SZMB

It's possible that the leak is so slow that they can't detect it. If the problem occurs again next summer or even later this summer, you know the leak is there.

MB211

A slow leak will show up with the dye added. Have it rechecked in a couple thousand miles. Very easy for the tech to follow a/c refrigerant curcuit with the light to inspect for leaks. This was if it is leaking, you can get it repaired before running out of warranty.

konigstiger

If documented on invoice attempted repair is covered for 12 months/unlimited mileage.

MBE550

I do have MB's extended warranty for 3 yrs starting sometime this month.
Sometimes it's hard to tell what's covered under this warranty.

mohsinazmi

I know this is an old thread but I am having the same problem with my 07 and I have a couple of questions regarding charging up the system. So I found the low side by the driver's side firewall which was covered with a black top. I wasn;t sure if this was the low side or the high side but when I connected a gauge on it, the numbers were pretty high like in the hundred so I knew it wasn;t the right side. Also If anyone knows where the low side is, it would be great! Also the correct pressure would be much appreciated.

Thank you in advance

Efivehundred

The low side is the larger diameter pipe and the high side is the smaller diameter pipe. Both service ports are next to each other on the driver's side of the engine bay, from what I've seen.

In the climate control display is "AC OFF" displayed? If it is, when you press the AC OFF button does it flash several times?

A hundred something PSI on the low side is normal for static pressure, meaning the compressor is not operating. If you want to charge the system the compressor will need to be operating.

mohsinazmi

When the A/C Is off it just says "OFF" and yes that was pressure when the compressor was off but when it was on, the pressure was in the in the high 100s meaning around 180-190. I have to go home and check if it flashes. Does the A/C has its own diagnose mode where it would display error codes? I used to have an Audi and on the A/C unit on that one you could check the error codes by pressing a couple of buttons on the actual AC Display. I don't know if there is a way to check on this model.

Thanks Again

Arrie

Old thread but...how does it work? How do passenger side vents blow cold air and driver side "kind of cool air but not cold" and the problem is low refrigerant?

Does this car have two compressors/systems, one for each zone? I don't think so...

mohsinazmi

The Old Audi had the same symptoms and from what i understand is that since the freon is being warmed at the evaporator it gets warmer faster since there is less of it so by the time it reaches the further end which would be the drivers side, its already warm so its not cooling the air like it should. atleast thats what it was doing in the Audi but I believe the basic principle is the same.


By no means am I a HVAC tech but this is what I think happens. Please correct me if i'm wrong

Thanks again

vettdvr

Over the last 40 years my experience with auto a/c is that even a new compressor can leak up to 2 oz of feon / yr. Over 5 yrs this is 10 oz and enough to effect the system without having a major leak. Mine quit cooling after 7 yrs and it never had been "topped off". Dealer recharged and all is well no other parts or work.

I would have added the freon myself but I was on vacation 1500 miles from home with no tools.

bpsturbo

Im in Dallas and I have a black 2005 E5 with black leather so it is painful to go anywhere right now but I have to go for treatment (Cancer) 4-6 days a week. Please, help if possible. About a month ago I lost power intermittently.. Like the engine was stalling or bogging down. About 2 weeks ago it got painfully worse and the air on the driver side began blowing only hot air while the passenger side remained cool. Then about a week ago both sides began blowing hot air and when I push the AC button the light flashes then off.

felixromero

Same problem on my 2003 E500 passenger side front and back ice cold, Driver side front and rear kind of warm to hot.... Any ideas?

bpsturbo

The charge is normal. The line was blazing hot though. Thanks, in advance for any help.

joetarin

Adding more refrigerant always correct this issue. I had the same problem last week. I went to autozone and bought a $30 can of R134 (including the hose and gauge) and put about 1/2 the can in. Fixed it right up. I keep the remaining can in the trunk because you never know. I just had my AC serviced and there was a leaky valve that was replaced so I"m not sure why I ended up low again, I chalked it up to maybe they just didn't refill it enough. Either way, this fix was much cheaper than taking it into MB.

felixromero

Could you please explain the steps on how to add R134? I am kind of ignorant when it comes to how the a/c works...And also where is the connector to add the freon?
Please help.
Thanx