Hello all. I have a 2015 V6S with some AC troubles. About a month ago I noticed that about 1 in 10 times that I started the car, the AC would blow warm until the car was properly warmed up. It was as though the compressor was not getting the signal to engage. Once the car was warmed up, the AC seemed to work as intended, blowing cold air as needed. I took it to the dealership and asked that they take a look and see if they could figure it out. They claimed it was low on refrigerant and they topped it up after confirming that there are no leaks. When I picked the car up the same exact problem was present.

The next solution was to replace the compressor, as the thought was that the internal pressure witch was the culprit. That was done, I was assured that everything was working and I picked up the car. It was not working. Now when you start the car, it blows warm air, the compressor engages, the RPMs dip, the car lightly stumbles, the compressor cuts out and then the car recovers and runs smoothly again at +/- 700 rpms.

So I took it back and they reflashed the HVAC software module. I was told the car had been driven several times, had been left to run in the shop and that there were no problems, everything is working great. When I picked it up I discovered that the AC doesn’t work still with the exact same issues and symptoms as before. AC doesn’t work at idle until the car is warmed up or the RPMs are up over about 1000. Otherwise the compressor engages and releases and the rpms dance around accordingly. To me it seems as though there is a bad sensor somewhere, or that the compressor they installed is bad. Anyone have any experience with any of these issues?

I'm starting to get a bit frustrated. Unfortunately, I am kind of wed to the dealership on this as they did the work under a warranty that has since expired and I'd like to spend their money instead of my own.

 

No real help to you but I would take it to a different dealer. No way it can be low in refrigerant without a leak as it is a completely sealed system. Either it has a leak or it doesn’t. They either lied to you about being low in refrigerant or they lied to you about it having passed the pressure/ leak test I suspect. New compressor shouldn’t fail so maybe more refrigerant has leaked out since topping up.?? .Sound like they are just throwing different excuses for the solution and using a shotgun approach .

 

Or find an AC specialist who will likely know more than a dealer.

 

They did a leak test on the system and found it doesn't leak. Then they refilled with refrigerant. Then they said it was a bad sensor inside the compressor, for which there is a TSB.

I can't take it somewhere else unless I want to pony up the cash. I'd rather have the dealership fix it as it will be on their dime.

 

Have to ask: Do you have the HVAC set to AUTO?

Depending on ambient temps at the time of startup, your car may not feel that A/C is required right away. Our F does this when we leave our relatively cool garage, on a hot day.

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Try moving the center FAN dial to another setting (this turns AUTO off) and tell us if this changes the behavior.

 

Yes, I understand how the system is supposed to work. The temperature where I am is still warm. Yesterday was 85 when I started the car for the first time in two days. It makes no difference how the temperature is set - auto and moving the dial to LO does nothing to make the air colder. I went to the AC controls in the display and tried changing the flow to each zone and there is no change.

This car is my daily driver so having the AC work in Washington, DC is important.

 

I see you changed the AC compressor but what about the DPS?
Have you seen this TSB?
Has the DPS been changed?
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Yes, I brought this their attention and was told that pressure switch is and internal part of the compressor, hence the change of the compressor. I have just sent it to the service advisor again to see if that's actually the case.

Thanks

 

OK glad to hear it!
The new compressor should have the latest and greatest stuff in it too.
Hope you find the problem?
Could be a bad new compressor?
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That's kind and of my thought at the moment as well. I am dropping it off again in Monday evening - hopefully they can figure it out.