When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
A few months ago my A/C was weak, then nothing. Prior to this, the left (driver side) vent and left-center vent were warmer than the passenger vent and right-center vent Took it to the dealer for a proper evacuation and refill. They said they added dye. Left the dealer and it was cold, but still some temperature differences in the driver versus passenger side vents.
Fast forward a few months and the driver side vent is warm, along with the left-center vent which measure 82' F and center vent is 81'. Center-right vent measures 63' and passenger vent reads 67'.
I was thinking it might be the duo-valve, but wanted to run the built in diagnostics. When I follow the procedures to do the climate control test, I only get one error. It read "E TF" As I cycle to the next code, nothing comes up, same error. This happens when the car has sat overnight as well as after driving for 30 minutes in 95' weather. One issue is my pixels are sometimes missing on the climate control unit, so the "T" portion of the code on the right side is missing the top-left ortion of the "T", so it looks like a lower case R....hope that makes sense.
Plutoe....did you read the part I wrote about not be able to get any codes from the climate control unit?
I wrote, "When I follow the procedures to do the climate control test, I only get one error. It read "E TF" As I cycle to the next code, nothing comes up, same error. This happens when the car has sat overnight as well as after driving for 30 minutes in 95' weather."
Not sure what to do when I'm not getting any useful info out of the climate control test. PS...I have done the test before on my other w210, I know how to get codes, but nothing is appearing on the unit. Any help?
it is still unclear and it may be due to semantics and vocabulary. aside from the trouble codes which you say you already have
I'm not clear if you have already identified the VALUES for in/outside, evaporator, engine cooling, refrigerant pressure etc etc.
I am only reading that you have codes which, to me, are not the value readings. If you have the values, do post.
kajtek, is this something I can do on my own? Is there a way to check from the climate control unit? I am obviously not very versed in A/C systems. Someone else suggested it could be a 'flap' issue...not sure about that. I did notice that when I first start the car after sitting over night, the passenger side blows cold, but the driver side never seems to get any colder than ambient temperature. I just know
Do the calibration test, not speculation.
Everything is relatively easy to fix on those systems and if you can replace battery on your cellphone, you should be able to DIY the fix.
And ignore spammers.
Still wanting to know how to do the calibration test. Will likely need to take to the dealer and get these lines changed? I see dye. Any idea of how labor intensive this is? I don't want to necessarily mess with my A/C lines, R134, etc. This was the only dye I could readily see. This is behind driver side headlight This is a close up behind the driver side headlight This is on driver side of engine up to near an A/C port
Calibration test is reading all (temp) sensors in the morning when everything is cool and suppose to have the same temperatures.
Your pictures show dye around fitting, what means the orings might be bad.
Wash it off and recheck after some driving.
Did you put dye in? You have plenty of refrigerant in the system, so something else was going on?
I wasn't aware of a calibration or reset or alt-ctrl-del sequence but after reading this thread, I was
intrigued and read multiple 'reset' instructions which were more of the easter egg flavor. I tried it
several times but unconvinced simply because I wasn't able to activate this on my 99 E320. could
be user error - dunno.
(the easter egg involved pressing front DEFROST and RECIRC buttons simultaneously. I'll let you google for the discussions yourself)
I think the calibration terminology is incorrect as I think the intent is to suggest getting a base line from the sensors #3, #4, and #5 prior to pressurizing the AC system. AFAIK there is not a method to reset the sensors. If the values are off before then there would be a problem getting good data during AC operation.
The compressor line looks like an o ring which is relatively easy to access to change by disconnecting the torx bolt.
The other line comes off the drier but the other connecting point is at the expansion valve under the wiper tray. You'll need to disassemble all that including the wiper motor assembly, which isn't hard but requires some patience. The hose needs to be replaced as it's leaking at the crimp point.
Evacuating the system is the tricky part and the rest is mainly labor. If you decide to do this replace any o rings you see and use the right metric allen wrench to disconnect the hoses from the expansion valve.
Last edited by Tall Giraffe; Aug 16, 2019 at 04:35 PM.
This is the case where keyboarding google takes over common sense.
Reading the sensor at the time when all temperatures should be the same is calibration test. End of the story.
I understand that not everybody can understand technical principles, but that should not be excuse for all that senseless whining.
Plutoe is excused becouse of his role here
Thanks everyone, I appreciate the help and comments. So I know I have a leak as shown by the dye that the dealer put in a few months ago. Also, I ran the test when the car was driving and sensor 7 was reading 4 to 5. Today it was at 1.
I have no way to take out the refrigerant, and that one hose that needs to be replaced is something I'd rather have and expert handle. I wonder how much a shop/dealer would charge to do the O-ring and replace that hose? Dealer charged $125 to evacuate and refill, so that is a known price.
I did the sensor test right after starting the car, here are the numbers.
1---5
2---56
3---02
4---71
5---02 0r 60 (I have bad pixel on climate control
6---159
7---15
8---141
9---28
At 1 point you report pressure at 1 bar, at another 15.
Even considering that 1 is with engine off, the other is not possible.
The same with reaching 2F in your system. Something stinks here.
Dealer will not change oring only. Usually they do whole component replacement, what can easy reach 4-digits in estimate.
So right now it is 88 degrees here. I go out to my car and with the key in position 2 (not starting) press REST for 5 seconds to get a read out and my #3, #4, #5 and incidentally #8 are all within a couple degrees of the ambient temp. Yours should be the same as your ambient temp. My #7 is at 6 ( #7 slightly varies depending on your temp outside) with proper charge and new system front to back replaced this year. Do this when your car is stone cold.
This is what you need to do to determine if your sensors are measuring properly before starting your car.
Maybe Im missing something but IDK how you are producing so much pressure, your #7 at 15 bar with so little refrigerant if you say it initially read 1 bar?
At 1 point you report pressure at 1 bar, at another 15.
Even considering that 1 is with engine off, the other is not possible.
The same with reaching 2F in your system. Something stinks here.
Dealer will not change oring only. Usually they do whole component replacement, what can easy reach 4-digits in estimate.
Agreed.
And you know with the broken pixels, they may say a new climate unit too!!
Damn, hopefully it's not too bad. I have found a good indy who will look at it and do the hose and fitting and look for any other leaks/dye.
So the car sat for 2 days....Before I started it I ran the test again. Keep in mind, the bad pixel is the first digit on the right side, so "05" could be "85". I know, this isn't helping at all, so apologies. The shop has the STAR tools/software, so I assume they will get accurate values. With that said, these are the numbers from this morning using the "key in position 2 (not starting) press REST for 5 seconds " method Tall Giraffe listed.
***Keep in mind, the bad pixel is the first digit on the right side, so "05" could be "85" or "65"
1...05
2---04
3---05
4----05
5---07
6---07
7---07
8---04
So what was your ambient temp when you took the measurements? The last digits look within similar range, a couple degrees, so they may be reading ok.
If those pics you shown were the only leaks then the hardest part ot repair is the line off the drier, which isn't terribly hard. It requires, recapturing the refrigerant, removing the washer tanks, removing the windshield wiper cowl and wiper assembly, disconnecting the expansion valve, then disconnecting the line from the valve and drier.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
