Manton

Hello and before I explain what my issue is let me just say that I have searched and searched this site as well as other sites and it seems like everyone has different opinions or not an exact issue I have. If anyone had similar issue with their AC Id love to hear your opinion.

It started as AC cutting out and switch to blowing air full blast from the defrost vents while driving. It would only do that If Ive been driving my car for an hour or so in hot 105 degree weather. AC runs great when I first start the car in the AM but as soon as It starts to get hot outside It does this weird switch between AC vents and defrost vents. I tried holding the two buttons "recycle" and "defrost" to reset the system, however the lights never stopped flashing (I am assuming you are familiar with the reset) so I took the key out, started the car a minute later, and AC went back to normal. After few minutes of driving, the AC shut off but this time it didn't switch to defrost vents it just completely stopped working.

Now my AC doesn't even come on in the AM, like at all... I can hear the compressor kicking on when I turn AC on but there is no air coming out. When I turn the "auto" AC function I can hear the electric fan kicking on but once again the AC is not blowing any air.

Now from what I understood It can be the blower motor which is under my glove box? or the blower motor resistor?

I checked fuses number 30,41,51 and they are all good. Are there any other fuses I should check? I am trying to eliminate all possible issues I can do myself before I take it in. Could it just be out of freon or is there a way to do a reset besides the one where I hold two buttons?

On a side note I just remembered that while I was driving my AC turned on and off by itself like 4 times in a 20 min period.

Id appreciate any help, thank you.

Amir_AMG

most likely culprit in my opinion is the blower motor/ possible combination with no freon. You can take it in to a decent indy shop and have them check and fix it.

here is a handy link from benz w0rld

http://www.benzworld.org/forums/w209...ml#post5351978

admin dont know if this is allowed? if it is please take down the post.

Amir_AMG

see the attachment on how to get to the charcoal filters the blower motor/resistor are right there

Rudeney

If the RECIRC and FRONT DEFOG lights don't stop blinking after the test, then you have a fault code that needs proper diagnosis. SDS and other specialized tools can read codes from the ACC to tell you exactly what's wrong.

Manton

Thanks guys! I have an apt at the dealer on Sat to run diagnostics....Man I couldn't believe they wanted $129 just to read the codes... They said that Autozone code scanner tool would not detect the issue, is that true?

xsever

Yes that's right. The Autozone code scanner is a generic one which cannot ready MB-specific codes which need MB's STAR/DAS scanner.

Manton

So MB dealer id the problem. Blower motor and regulator, they are asking $1400 to fix it... Um no thanks lol. I went under my glove box, took out 5 screws that hold the motor with the regulator, took me 2 min. Now Im waiting on the parts to get here.. ordered them from rockauto.com which only cost me little bit over $150. I still cant believe the dealer is charging $1400 for 5 min worth of work and less then $200 in parts. Anyway I will update the result once I put the new parts in.

Manton

Sorry took a while to update. Anyway I installed the new regulator and blower motor however the problem was not fixed. Ac still did not turn on except I would feel little bit of air coming through the defrost vents, very small amount not even enough to move hairs on your arm. So I took back to the dealership and they wanted to do another diagnostics to check for any other codes, turns out it was the sun sensor the whole time. Parts and labor at the MB dealer cost me $328 out the door and now my AC works how it should.

My advice to everyone is that If your AC starts doing crazy things like switching between vents or stop blowing randomly then turns on again or stops completely, check the sun sensor first before you start spending money on a new blower and regulator.

P.S. Im just glad it wasnt the flap motor...Dealer told me to replace one of those is about $2500 FOR ONE and my car has 6 If i am not mistaken.

Rocman8

the "reset" that you are doing with the 2 buttons is ONLY renormalizing the stepper motors. since the lights dont stop flashing there is a problem with at least one of them and there is probably a code stored which is why they said to repair it. most of the repair cost is in the labor not the parts but 2500 is even high for a dealer. even if the dash has to come out no way labor should be more than 1200.

Waz786

Hi guys I have a c63 amg year 2012 an noticed yesturday that the fan was runing at full speed while the cars on an it does it even when I start her up from cold start. I also noticed that the ac isn't giving cold air now any ideas what can be or how I can solve this issue many thanks

Rudeney

My SL550 did this today with the fan (though the AC was working just fine). It would even run the fan for a minute or two after shutting off the engine. Normally this is a symptom of the ECU not communicating with the fan controller, but I scanned for codes and found an error on the engine temperature sensor. I cleared it and all was well. I also re-seated the connector on the sensors we'll see if it returns.

So, step one - scan for codes.

Patton001

I suggest you buy the iCarsoft i980. It reads all of the MBZ codes and only costs around $110. I found one under $100 when I bought mine with a little searching.

CDM Motorsports

if your are going to buy one buy the MBII, of $199. the little extra money it does allot more than the i980

Rudeney

Or go about $250 and you can get SDS.

Waz786

thanks everyone for ur replays so I took the car to Maine dealer an they found that the ac fan was runing excessively because my temp sensor was faulty along side the ac control unit so they have changed it under warantee I will pick the ar up later an will let u guys know if anything does change thank god for warantee lol😊😊😊

jdsilver560sel

Hello all, has anyone found a company that makes a better replacement fan control speed + - Plus Minus button Thanks in advance I've seen a link to Sunlover975@qmail.com that's inop

Ann Kennedy

I have a Mercedes 190-E Sportline imported from Japan. The Mercedes dealer can not fix the AC. It is a fun car to drive except in the summer heat. I would drive him more if the AC worked better. It is alright at 80 degrees F but a disaster at 100!

Rudeney

Your car is a W201 - you should post in that forum as you are likely to get more qualified answers. However, your problem is common across most cars. If you have the skills and tools, check the pressures on the system as a first step. You may just be low on refrigerant. If the pressures are correct, then you may have a clogged condensor, or cooling is fine at speed, but not when stopped, you may have a problem with the engine suction fan not pulling enough air through the system. You could also have problems with the dryer or the expansion valve. But at that point, you may be needing some ahnds-on, professional assistance.

ot1

Daniel123

I have a 2010 GL450 having problems with front air suspension on driver side every time I park the car it goes down on the driver side, looking in to the conversion kit do they work ? or will there be a problem on the screen saying compressor not working or some thing ?

jbodentrader

2000 E430 260K miles, A/C quit last week.Ran diagnostic check #7 Refrigerant Pressure reading 0. I have 2 questions. 1., where is the sensor located and 2., when I locate it can I change it myself without spraying R134a all over the place? I called the local stealership in Haverhill, MA and they refused to even tell me where the sensor is located.

rmetzner49

On my CLK350, the pressure sensor is located on the receiver/dryer/condenser. Follow the AC lines to the unit in front of your radiator. Right there at the disconnect point, there is a sensor. You may have to pull the underside plastic pan to see it.
Unfortunately, it DOES mean you have to dump all the Freon in the system to change it. Please be responsible and have a local A/C shop reclaim the Freon. A local shop charged me $20 to do it. Simply recklessly discharging it is a Federal offense.

jbodentrader

rmetzner49, thanks for the info. I will check for it today. I replaced the radiator a few months ago, maybe I disconnected the sensor unknowingly.

rmetzner49

That connector in particular pops off of the sensor fairly easily. Most connectors on the car have a fairly elaborate latching mechanism. This one has only one little tab and releases with little fuss.

I just finished a week long effort and replaced most of the components in my A/C including compressor, condenser, receiver-dryer and expansion valves. My high side pressure was only reaching 150# when it should have been 225.
Living in Florida, you can't afford to have your A/C only working at 2/3 capacity.

doctorroboto

It was a bad compressor, just to close out my earlier topic.