My '06 Mazda 6 is having weird issues with the air conditioner. It cools normally most of the time, but sometimes when I stop and the revs go down it stops cooling. The fan keeps blowing but it's not conditioned air, like the condenser? is shutting off. If I rev the engine or start moving, it kicks back in. I really don't know anything about car A/C's, so any thoughts are appreciated. My only guess is a voltage problem. I took it to the dealership multiple times, but of course it would never do it for them. Now the manufacturer's warranty is up and my extended warranty doesn't cover electrical problems, so I'm hoping it's something that I will be able to fix myself once I get it diagnosed.

 

Hi there, are you saying the compressor stops working ? Ie , it should kick in and out that is normal operation , the system is fitted with a tripple pressure switch i think this might the problem, or not enough refigerent in the system.

 

INFORM your mazda dealer to perform a system pressure test and a A/C performance test, tell them they will find the correct way of doing this on MESI located on Portal . (Only in the U.K)

 

i guess master was right, probably you have a low refrigerant. with out rev, the gas in the system wont reach the minimum pressure to turn the pressure switch on. that is why compressor getting off when you're in idle position.

or it might be your cooling system, cooling fan is blowing the condenser to cool on the gas... but if the cooling system is poor there will be and high pressure on the the system that might turn of the pressure switch and compressor as well.. you can also check your auxiliary fan, for proper operation.

 

That can be caused by the engine primary cooling system. There is a protective interlock between the engine temp. control/sensing and the A/C compressor such that if the "brane thing" decides your engine temp. is on the high side, it will cut out the A/C compressor so all the compressor load is dropped and all available cooling fan capacity is devoted to engine temperature control. Typically, the engine temperature peaks shortly after you've run it hard and then you stop and idle. This matches the symptoms you describe to a 'T', and suggests you should have an overall engine cooling system tune-up and performance check done before embarking on an A/C system teardown.
The fix can be as simple as doing an overdue radiator flush/ radiator core hosedown or a water pump drive belt adjustment/ replacement.
The ethos of today seems to be to replace everything in sight, resorting to a bit of TLC only as a last resort. Don't join the crowd and let the "brane thing" keep the NAPAs, Autozones etc. rolling in cash.

 

I'll keep all this in mind. Haven't had time to get any diagnostics done yet. I'm a new father and the evening time is my "shift" hehe. I don't think it is my cooling system though. Haven't had any problems with the car getting hot and it has been on quite a few road trips in the 90+ degree south Texas heat, plus the normal stop and go around town trips and the temp stays in the normal range. The a/c will act like this right after I start up the car, before the engine has even reached "normal" temp. As for replacing everything in sight, that is definitely not my style. I fix only what needs fixed and keep up on regular maintenace. It's much easier on the wallet, and that is extremely important right now thanks to the outrageous costs associated with bringing a baby into the world, even with health insurance. Thanks for all the tips and I'll keep an eye on the board for more. Hopefully I'll be able to get a diagnosis in the not too distant future and get the problem taken care of. For now the a/c is still cooling and a quick rev gets it going again when it cuts out, so it's not the highest of priorities. If it was an engine, brake, suspension, etc. problem it would've already been fixed.