Air-con weird issue

Page may contain affiliate links. Please see terms for details.

clk320x

Hardcore MB Enthusiast
SUPPORTER
Joined
Sep 27, 2016
Messages
12,987
Location
UK
Car
Tesla Model S, Model X & Mercedes W212 /// Previous: Jaguar XFR, Mercedes E320 CDI, C32 AMG, CLK 320
Hi guys,

My air con works ice cold for a while then starts fading away... if I then turn off the AC button and turn it back on in a few seconds it will work again for a while...

It's been regassed and 750g of refrigerant put in, 5cc of oil and 3cc of tracer die. It was vacuum checked and there were no leaks...

Anyone have any ideas?

Cheers
Abs
 
Can't quite answer but, where did you go for the previous work? Mine doesn't seem ice cold like my BMW was, it's lovely cold when the weather in general is cool. However on a baking hot day it definitely isn't ice cold, kind of fades out after a while

Did you go local to Northants?
 
Can't quite answer but, where did you go for the previous work? Mine doesn't seem ice cold like my BMW was, it's lovely cold when the weather in general is cool. However on a baking hot day it definitely isn't ice cold, kind of fades out after a while

Did you go local to Northants?

Yep mobile service to your door I will pm you buddy

Edit: you have PM

Also Ash I finally got some LED error free Sidelights nice and white perfect colour... £6 delivered if you need a link gimme a shout

Cheers
Abs
 
Last edited:
Hi,
I had a similar issue on the climate control of my C43, there were a couple of air temperature sensors/switches, one on the heater matrix and the other one on the Evaporator, if one of these fails it will cause the symptoms you are describing.
On some Heater control units there is a way to interrogate the sensors which would confirm this. Failing this it will need to be plugged into STAR to interrogate the A/C System.
 
Hi,
I had a similar issue on the climate control of my C43, there were a couple of air temperature sensors/switches, one on the heater matrix and the other one on the Evaporator, if one of these fails it will cause the symptoms you are describing.
On some Heater control units there is a way to interrogate the sensors which would confirm this. Failing this it will need to be plugged into STAR to interrogate the A/C System.

Hi buddy,

Do you remember how to diagnose it using the heater controls? I also had the heater control unit swapped out with a Facelift one from another car as the dad was facelifted

I think it can't be the climate control unit tho as the AC light comes on and stays on ?
 
The intermittent issues are the worst

Oddly it was colder before the regas :( weird ay
 
Abs, sorry to hear about your a/c problem.
I bought a [clone] diagnostic multiplexer as suggested here recently, no idea if it will pick anything up, but you're more than welcome to try (unless you have access to a STAR machine)?

Chris, thanks for the link - just ordered those :thumb:
 
area51 said:
Buy yourself this LASER - 4907 | LEAK DETECTION GLASSES | eBay? and have a look for leaks. Mine was cold until the weather got really warm then it just sort of gives up. Checked it for leaks and found that the condenser had 2 large leaks and several pinholes :(

Now these look damn cool, cool as in I can do a Gordon Ramsay at every hotel I'm going to stay at from now on... checking the bedsheets and carpet for stains!
 
Abs, sorry to hear about your a/c problem.
I bought a [clone] diagnostic multiplexer as suggested here recently, no idea if it will pick anything up, but you're more than welcome to try (unless you have access to a STAR machine)?

Chris, thanks for the link - just ordered those :thumb:

Hey David,

Thanks that's greatly appreciated, I'm just gonna keep using it till eventually it fails altogether and that way it'll be easy to source the issue. I hope :wallbash:

Thanks again
 
When I got my leak detection glasses I unscrewed both the UV lights, they are much easier to use then as it is possible to get them closer to pipes/hoses and into the corners of the engine bay.

I also found it much easier to see the leak detection dye by waiting until it was dark. I removed the cap from one of the valves to familiarise myself with what the dye actually looks like (it's rather like a glow-in-the-dark yellow).
 
UPDATE: it works perfectly icy for unlimited time when on AUTO with the temp set to the lowest one???

I did replace the climate control unit (all switches on dash) as the dash was facelifted , could the climate control switches be faulty???
 
Duo valve?

Don't think Clk has one?
 

Users who are viewing this thread

Back
Top Bottom