PontiacBonnevilleClub.com

Alright so this is how the story repeats itself on a daily basis. Get in the car, turn on the A/C. Get fresh and cold air for about 10 minutes when the cold air stops coming. The little A/C button refuses to do anything and the climate control is stuck in A/C OFF mode. Compressor will not engage. Time passes, yada yada yada, Carl drives around pissed and hot and out of curiously clicks the A/C button and whadaya know, cold air begins spewing forth from my vents. Obviously don't have a freon leak or it would have all been gone by now. The condenser did have some damage from the accident but if it was bad enough to cause a system failure, then how would my A/C be working on and off like this? Any thoughts/ideas are welcome.

Shot in the dark, I didn't know the CC unit had any impact on this situation when you told me. MAYBE could be the CC unit itself?

Alright so upon further experimentation today, I don't think it's the CC unit. If I set the windscreen defrost on, it still says A/C OFF and the A/C OFF will flash a couple of times if I press the A/C button. Although, what I noticed is funny is, the corresponding beating on the car as a result of the anger created by the A/C not working (WOT then slamming on the brakes kinda hard a couple times) made the A/C come back on, and cold air started flowing once more.... WTF

Could still be a bad wire in the CC unit somewhere maybe... Worth a shot at a junkyard part maybe. That or Penny's messin' with you.

Alright. So after swapping Climate Control units, the problem persists.
Anyone have ANY advice? This is really bothering me since I just dished out money to fix the AC last May.

My half-assed shot-in-the-ballpark guess: electrical issue with the compressor itself. Some switch or sensor there is having a short of some sort.

Hopefully somebody more knowledgable will chime in...

Ken_W

If it is something with the compressor or the like, take it to the guys who did it and see if they will warranty it.

did you check all the electrical connections for the AC (compressor, Low/high pressure cycle switch, ect)? I would have the pressure tested on the high and low sides to see if the pressure is the issue (low pressure would not allow AC to come on). It could be a issue with the compressore, LPS/HPS, low refrigerent, blown fuse (did you check all your fuses?). all that is telling you with the AC OFF is that it is not opperating correctly. the vehicle should have 2lbs of referigerent in the system. unfortunatly the only way to find out is to have the AC system checked with the right equipment. I dont believe there is a sensor on the condensor, but i would check for one just incase, damaged wire from your accidend would give you inconsistant "Fixes" (like slamming on your brakes)... causing the wire to ground or shake it loose from being grounded.

Mine just stopped working, Orifice tube is plugged from Compressor self destructing... now i bought a new Comp., Orifice tube, reciever dryer and might have to replace the condensor depending on how gummed up it is.

S

@redzmonte - I don't think low refridgerant pressure would affect the defroster, would it? A compressor problem most certainly would, which is why I'm thinking the problem lies in that area.

It would, as the defroster kicks on the compressor to dry out the air as well above a certain temp. The first step is to verify you first have proper pressures in the system.

The symptoms you describe could be caused by low refridgerant, which would be detected when pressures are checked.

Thanks for all the advice guys! I will check the pressure's hopefully tomorrow and get back to you all. FWIW, the A/C worked all day yesterday, and for most of today.

Your Pene and my Bonne are long lost twins with the same problem. Mine works great then not, for no reason it stops then starts again. Lets get more technical about it. The PCM gets info from a few things and determines when to turn on the compressor via relay 32 and the high speed cooling fan 2 via relay 37. I think they're both to be on at the same time. Turn on the AC, pop the hood and check to see if the fan(s) and or the compressor is on. The PCM provides a ground for relay 32 to turn on the comp.

Good night, more later

AJD

the second cooling fan should IIRC be running when the AC is on so i believe your statement is correct.

An AC testing machine can not only check how much freon is in the system, difference in pressure on hi/low side (which is what failed on mine proving my issue) but also can be evacuated and provide a vac leak test to prove a leak (faster then a pressure bleed off test). I would agree to start there.. if that all checks out then that will elimiate alot of things.

on a side note, i got a Variable orifice tube (for 105+ degree weather) to help keep the car cooler (mostly at idle, but can cool the system up to ~10*). I will post if it made any difference.

S

So I scanned for codes today and got:
P0530 A/C Refrigerant Pressure Sensor Circuit Malfunction

Does that help with anything?

I would bet on a bad sensor... A/C Refrigerant pressure sensor to be specific...

Advance says they have one available. As for where it is, I don't know. But could figure it out given some time I'm sure.

http://shop.advanceautoparts.com/webapp ... 60000_____

Pressure sensor is on the high side manifold pipe near the compressor.

Thank you!

Thanks!

My question now, and I'd bet Carl's too, is does the system need to be de and re pressurized to complete this job?

The pressure switch can be changed without evacuating the system.

That's what I thought would make sense, just wanted to be sure he knows before he goes to replace it.