Went to use my car and found that the A/C system is putting out HOT air. Made several attempts to select several operating conditions from auto to manual low temp and no change. I plan to do a little searching but wanted to see what input I get before I begin. My first check Is to see if the refrigerant is at the right pressure and levels. This system was working well about a week ago when I last drove it.

 

Sounds like yet another of the common faults, such as DCCV. Many threads on here for you to read

 

DCCV failure is certainly one potential cause. Others include O-ring failure (allowing your 134a to escape) as well as compressor failure and condenser failure. I hope it is simply an O-ring for you. First things first, though - check your fuses....

 

Assuming your refrigerant levels are OK, then as Jon mentioned try the cheap things like fuses first. However, the most likely culprit is the DCCV. This also seems to take out the ACCM in several cases, at least it did mine. Luckily for me it was all fixed under warranty. If the ACCM is bad you might be able to repair some of the circuits. There is a thread on that as Jagv8 mentioned but it may take some searching for it.

Good luck,

Mike

 

I did take a little time to look up the problem and found several suggested problems. 1- DCCV resulting in the ACCV burning up. Does this apply to 2000 S-Type? 2- “O” rings going out on the compressor, 3 – A leaking system, 4 - The compressor. I had seen a post that the cabin sensor was cleaned and the system began working. I am not sure of this, but if it is possible what application do I use to clean it and does it need to be removed?

John, I was unable to access the link you provided. I was never an A/C guy because I never had reason to go into it but I guess I will be digging into it. I have a set of gauges and plan to begin using them. I have a lot of homework to better understand this system and with a little luck it I will find the problem quickly. And I will check the fuses!! I learned my lesson a long time ago.

Any additional ideas please let me know. My best resource has been from the people that have been there and done that.

Any links on a crash course on charging the system? I have the general idea but would like a little reinforcement.

 

There are some good sites about a/c.... I just googled and they were so easy to find I didn't even bookmark them, sorry. First thing is measure pressures (high & low) when engine's been off so they're equal (or should be). Then start engine and watch pressures. Low should drop and high should head for about 200psi. If the low keeps bouncing off about 25-30psi up to (say) 50psi quite often and the high doesn't go up to (say) 175, chances are it's short of gas. It bounces off the low-pressure cut-out, trying to pump the high higher.

If you add, I would not add the kind that has any extra stuff (like sealant). Personally I wouldn't add stuff myself (certainly not when it's the first time you've had the car refilled), as it's so cheap to get a regular a/c shop to do a full drain and regas which also checks the seals for vacuum tightness and adds the correct overall amount of oil. The vacuum helps remove moisture from the receiver/dryer, too.

Back from the shop, I'd do a run with my own gauges to see what they read when all's OK.

Now, a couple of years later I might just add gas myself, rather than go to the a/c shop, if the gauges showed it was short on gas.