colbygil

I have a 2016 GLE350 and just recently the AC started blowing warm air. The clutch on the compressor is engaged at all times when the AC is turned on. At first the air would be warm periodically and then get a little cooler throughout the ride. Then I noticed if I turned the AC off and waited 5-10 minutes, when I turned the AC back on it would be blow cool for about a minute before warming up again. I checked the pressures and it was reading 60 psi on the low side and 175 psi on the high side. A good friend of mine works at an Acura dealership so I took it to him to have the refrigerant levels checked and we vacuumed out 2.42 lbs of refrigerant and put back in 2.37 lbs (manual calls for 1050 grams). After performing this service the pressures went exactly back to where they were previously. After letting it idle for about 15 minutes the low and high side pressure ended up equalizing out at 110 psi each. To me this points to a compressor failure, but I would like some input before throwing parts at it. I wouldn't expect a high end luxury car to have a compressor failure after 4 years but I guess anything is possible with a mechanical component.

I had also noticed through some research of people conducting a Climate Control Reset by holding down the air recirculating button and defrost button at the same time while the key is in the #2 position. This didn't produce any results like described in the procedure. Is there a different procedure on this model that I'm not aware of?

Any advice would be appreciated before I bite the bullet and take it to the dealership for a $160 diagnosis.

chassis

How did the pressure change from 175/60 when you checked, to 100/100 at the Acura garage?

The thermal expansion valve seems to be a potential cause. Google the thermal expansion valve, this has come up on this site before.

colbygil

The pressure change was odd to me as well. Right after the recharge the pressures were at about 55/190 and as we let it idle the pressure slowly began to equalize. It took a total of about 20 minutes for this to happen but it never would recover, even tried to run it through the rpm cycle. I will look for some info on the thermal expansion valves to see if that gives me some insight.

ItalianJoe1

The control valve in the compressor is sticking/failed. Very common on the later Benz vehicles and many newer cars actually. The variable displacement compressors have introduced yet another failure point and we have seen it many times.

The valve is not available from MB but is available from normal A/C repair companies, and is FAR cheaper than a compressor replacement, but does require removing refrigerant and possibly unbolting the compressor for access depending on model and engine.

colbygil

Thanks for the advice. Is the control valve for the compressor a bolt on part or is it internal to the compressor?

ItalianJoe1

It is part of the compressor but it can be removed, there is a snap ring holding it into the compressor. It has a small connector on it with 2 wires coming off, usually on the rear end of the compressor somewhere.

vsa

I know this is an old thread, but came across this as I had the exact same symptoms on my 2016 GLE 350 (AC blowing hot, compressor engaging, high and low side pressures about the same at 110-120 PSI).

Replaced the control valve ($50 aftermarket part), which fixed the problem. You have to recover the refrigerant first, obviously, but swapping out the control valve was fairly straightforward. While it's technically possible to access the valve from underneath the car with the compressor in place on this particular model, it's very awkward/tight, access to the c-clip is hard to get to at that angle, and you may not even be able to pull the valve out as it's both quite stubborn and there is very little clearance. I ended up disconnecting the AC lines from the compressor and removed the compressor from the car completely in order to more easily remove the valve and reinstall the new one (it even took some work to get the new one to seat properly - it should eventually click into place and the c-clip should fit in the groove so that it spins fairly freely once seated. Anyway, a little fiddly, especially getting the old control valve out, but as long as you have new o-rings at hand there is really no good reason trying to swap out the valve without removing the compressor first.

cupertino

W211 Ryda posted an excellent write-up with details picture illustrations for E class.
https://mbworld.org/forums/e-class-w...rol-valve.html

lancoranger

Good Afternoon, any chance you have a part # or information on the correct control valve? I have a 2016 GLE 350 and wanted to try this before changing compressor. But oddly enough I am having a hard time very finding the part.

Thanks

cupertino

Good day, I have a 2016 GLE350, it intermittently blowing hot air. a shop filled up the freon and did not find any leak.
diagnostic and says need a blend door under the dash will require 10+ hours to replace it. Part along is about $700 and labor is about $2400.
Does anyone have a DIY instruction or would Ryda's write up work...
================================================== ==============
W211 Ryda posted an excellent write-up with details picture illustrations for E class.
https://mbworld.org/forums/e-class-w...rol-valve.html

wildta

Dealer replaced my actuator in a MY2020, entire dash from inside vehicle had to be removed to replace a $35 part. I think labor was around 11hrs if I recall.

britoso

I just wanted to leave a note as I just went through a "blowing hot air" issue.

Here is how I caused the issue:
AC was not cooling as cold as It used to. I used two 134a cans and made sure the pressure was in the blue "filled" zone. Immediately I heard the system working harder and the vents no longer output any cold air. It was the ambient/heated air from under the hood.
Took it to a mechanic and he reduced the pressure from the low pressure side until it was at 60 psi.
The AC worked started cooling immediately!
Hope this helps someone, learnt that the GLE350 will not cool if the low pressure side pressure is too high.

​​

kajtek1

The proper pressure on compressor working at MAX should be above 250 psi high and 30-something low.
The 175/60 psi indicate wear our compressor, or control valve malfunction.
What's the mileage?
Than the description indicate that the system shuts AC off.
Do full troubleshooting.
Statt with sensors calibration test.
Go to the car on cold morning and without starting the engine, read all the temperature sensors.

juanmor40

Personal opinion here. That mechanic that adjusted a variable displacement compressor by releasing, or adding refrigerant w/o evacuating or knowing EXACTLY how much refrigerant is in the system should not be allowed to touch ANY AC system. Perhaps not even practice mechanics at all.

These are not the old-school AC compressors.

On the high side pressure value, it should be around 180->200psi, and it should as good as new. The low side pressure should be below 50psi, but there are no adjustments possible.

There is ONLY one process:
1 - Take pressure measurements when at operating temperatures, and diagnose likely failing components. Check for leaks when under pressure
2 - Empty the system
3 - Replace failing components plus whatever else required for an open AC system, like dryer and sometimes condenser. Check oil in the compressor is up to specifications. Be certain to account for oil in the system if not flushed.
4 - Vacuum as low as possible, and as long as possible within reason (not just 5 min)
5 - Charge to the exact amount posted on the sticker, or find the original specifications
6 - Retest to verify fix is working as expected: low pressure < 50 psi, high pressure >180psi < 200psi. At least those are the ones I see in Florida at the peak of the summer. AC for the W212 and the two W166 are working as well as they can do.
7 - Repeat if the initial diagnosis was not successful.

NOTE: early 2023, 2012 ML 350 was not cooling great: Symptom: driver side warmer than passenger side.
First fix (late summer 2022)
1 - Low on refrigerant. Indy checked and refilled (I was not there, so I can attest to follow procedure)
2nd fix (late 2022)
1 - Not cooling well, refill again.
3rd fix (Jan 2023)- This is me now because of the two failed attempts ( https://mbworld.org/forums/m-class-w...ml#post8699414).
1 - Measured pressures at operating temperatures, and noticed abnormal behavior between low and high. Low pressure approaching 70psi under maximum load instead of dropping below 50psi. This is not the typical behavior, and is not listed on every AC check list.
2 - Diagnosed to electronic control valve. MB does not sell it. DENSO does not either, and Toyota's is different.
3 - Cross-referenced several ECV on eBay, and Amazon and finally found the "correct one"
4 - Follow the steps above, new ECV, new Schrader valves, charged to the sticker specified value
5 - Works great.

lanomck

I'm really hoping you see this and can point in the right direction of this part because I can't find it anywhere. Tbh don't even know what to type to search for it or what it looks like. I would appreciate it big time

juanmor40

The above us just a generic compressor for MB, yours may look different.

The electronic control valve is the one with yellow dot. Yours may not have the dot, perhaps a triangle or nothing at all. Location should be similar

Post VIN, a photo of yours if possible, and I try to find exact photo.

lanomck

4JGDA5JB8GA804042 2016Gle 350

juanmor40

Compressor photo?

juanmor40

This car puzzles me. It seems it uses a non-Denso compressor.

I could not find a photo of these two options anywhere ( https://mbparts.mbusa.com/v-2016-mer...and-compressor)