: 2009 cts a/c

05-07-13, 02:10 PM
Warranty is off my 2009 CTS (60,000 miles on ODO) and it appears my air conditioner is done. Basically when it is turned on to the lowest temperature it belts out warm air. This is after years of the A/C coming on in the wintertime. Is there a way to check the status of whether it can be repaired or needs replacement without taking it to the dealer? Am surprised it isn't working we don't live in a hot climate, it is used rarely and the car is just 4 years old.

05-07-13, 02:31 PM
It`s a complex system with electronics & mechanicals, you`ll have to bite the bullit and take it "somewhere" for a diagnosis.
Whether that`s the dealer , a general repair shop or a dedicated A/C specialist is up to you.

As an example, let`s assume the compressor clutch is not engaging, could be:
1 Clutch is bad
2 System low on refrigerant ( has a psi switch to protect compressor
3 In car controls not sending a signal.

No 2 is common and now you need to find the leak:
Compressor seal ?
Hose or line ?
Condensor ?
Evaporator ?

Lots of possibilities...

05-10-13, 11:45 PM
Thanks 99flhr I guess I will take it in somewhere for a look it just seems so odd as I also have a 2007 Q7 which we use on long trips with the kids and often the AC will be running solid for 12-16h and we have had zero issues with it.

05-11-13, 12:10 AM
A/C is one of those things that is a hit or miss for any manufacturer because there are so many parts sourced from so many manufacturer's I've had cars go 10 years and still had original freon when I got rid of it and others only 4 years. Where are you located. I had to deal with some AC issues on other cars so if you're local I can help you with some minor troubleshooting. I have a freon leak detector that isn't professional quality but it helped me find a leak in the past was worth the $55 I paid for it.

C "T" ess
05-11-13, 12:01 PM
Before taking it to a professional to look at it, I would try to add a can of freon. Usually you can find the kit at any local auto store. Try adding the contents of the can. If the a/c begins working again; even if not arctic cold, then you know its a freon leak. Then you can be more informed and not blindly sold whatever the shop wants to get away with. If it is a leak, the shop will put a dye in and check later to determine where the leak is and go from there. Just my 0.02 cents worth.

05-12-13, 02:01 AM
Thanks OMG you bring up some decent points and to be frank this is the only vehicle (have owned many import/domestic) I have ever had an issue with AC so it really seems odd. If I were in the Mid West I'd take you up on your offer, I am in the Northwest on the Coast so it would be a bit of a hike to get to IL but again thanks.


C "T" ess, I may try that, it is an excellent suggestion thank you.

05-12-13, 10:37 AM
Refrigerant leak is by far the likeliest reason for your problems. You should be able to find a tech who can easily and inexpensively test for such a leak. Good luck.

06-05-13, 07:46 PM
So now it appears the a/c works intermittently. When it is working I can smell the a/c it is a different smell than just the air. It seems to work on acceleration but not always. I wonder if there is a belt from the engine that powers the a/c? Again, very odd as it does still work and when it does it is good, if it doesnt start right away it rarely gets going even if I stop and restart it.

06-05-13, 09:42 PM
Simple test, shut off radio roll the windows down, turn air on do you here a distinctive click and the compressor running? It might start short cycling very fast so listen carefully. You will here it. Under acceleration and as RPM go up it will drive the low side ppressure down, (why air is cooler when driving vs idle plus you benefit from better airflow across the condenser. My hunch is low freon due to leak and compressor is inop due to low pressures. Does it seem to work 'better' when ambient temps are higher? If you have any questions shoot.

I do believe its a one belt system so you'd have a lot of other issues.

07-03-13, 02:44 PM
Hi rspreng thanks for the suggestions I will get to it. HAve been off the board for almost a month with kid stuff. The prevalent issue remains, a/c intermittent. It seems as though on hot days when I need it the a/c does not work when day are more temperate it does work. So in answer to your question it is the opposite hotter it is less it works and vice versa. Could just be coincidence, Murphys law etc.
Did as you indicated and unit appears to be running but there was no a/c in the vehicle.

07-04-13, 06:21 PM
Thanks 99flhr I guess I will take it in somewhere for a look it just seems so odd as I also have a 2007 Q7 which we use on long trips with the kids and often the AC will be running solid for 12-16h and we have had zero issues with it.

Well, if it makes you feel better I had a BMW Z3 Roadster condenser take a powder @ 15000 miles, out of warranty, out of pocket $1000.
It`s just the way things happen. You fix what you can yourself or you pay someone who can.