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2002 olds bravada
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Discussion Starter · #1 ·
I had A\C last summer. Now spring is here and I don't. So before I go and do anything drastic I am asking for suggestions hopefully cheap ones. I have tried leaving the switch off for awhile then back on it acts like it wants to cool but at this point I am not sure. I do now that the dryer was hot not cold like it should be I also do not hear the compressor trying to kick in at all. I was wondering if a reset by disconnecting the battery might help or pulling a fuse or just beating the sh*t out of it with a hammer. Any suggestion appreciated. Thanks!
 

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2004 gmc
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You should be able to look at the front of the compressor, and see if the clutch is engaged and spinning. If it isn't, the problem could be electrical or mechanical.

Electrical problems might involve the HVAC controller, in which case, a battery disconnect might work. Or it could be a bad fuse.

But much more likely is a leak that took out your refrigerant while you weren't using it. Low pressure gets detected by the controller, and it disables the compressor so it won't destroy itself trying to pump nothing. You would need a professional to check pressures, find and fix the leak, and recharge the system.

2002 is getting old - how many miles on it, and is there a maintenance history of anything that might have dinged the AC heat exchangers or hoses?
 

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2002 olds bravada
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Discussion Starter · #3 ·
No issues that would lead one to think that it could have been damaged. I will check to see if the compressor is kicking in. It has about 88000 miles and other than a water pump brakes rotors and hubs never had a problem under the hood. I will try as much as I don't want to. Mainly because I might have to clean Throttle Body and there is a bunch of crap to remove just to get to it.
 

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2003 chevy trailblazer_ls
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You should be able to look at the front of the compressor, and see if the clutch is engaged and spinning. If it isn't, the problem could be electrical or mechanical.

Electrical problems might involve the HVAC controller, in which case, a battery disconnect might work. Or it could be a bad fuse.

But much more likely is a leak that took out your refrigerant while you weren't using it. Low pressure gets detected by the controller, and it disables the compressor so it won't destroy itself trying to pump nothing. You would need a professional to check pressures, find and fix the leak, and recharge the system.

2002 is getting old - how many miles on it, and is there a maintenance history of anything that might have dinged the AC heat exchangers or hoses?
:iagree:
My money is on low 134A, but I have been wrong before.
 

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... I might have to clean Throttle Body and there is a bunch of crap to remove just to get to it.
But you can comfort yourself the entire time knowing how much per hour you're saving by doing the job yourself. Even MORE if you realize that to pay the dealer $90 an hour (let's say), that's AFTER tax money from you, so you have to earn MORE than that at whatever your tax rate is.

Doing it yourself saves even more than people normally think because of the tax angle!

That makes up for the beer budget required for driveway jobs, even if you have to offer a couple to your friends to get them to help. :tiphat
 

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Air conditioner experts recommend regular short operation of the air conditioning cooling system, even in cold weather. Turning on the compressor every month or so lubricates the seals with the oil in the refrigerant and that keeps the refrigerant from escaping. If the compressor won't run it's probably a safety device keeping the compressor clutch from engaging so the compressor doesn't self-destruct from lack of oil.
 

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Discussion Starter · #7 ·
So the compressor is not engaging. I also checked all of the HVAC and A\C fuses. If this is due to low coolant is it possible to get a kit from say autozone that could tell me the pressure in the system before I fill it. If this is the case it would be much cheaper than taking somewhere which I can't afford. It would be a long hot humid summer with leather interior if I can not get the A/c working. I appreciate all of the fast reponses. :thx
 

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But I have to recommend not simply throwing cans of refrigerant at a leaky system, because in the long run you're going to spend more than paying a professional to find the leak.

In the wintertime, were you running with the AC button pressed OFF? If not, then the compressor was trying to run whenever the temp was above 34-35 degrees. Just intermittently, but in our vehicles, it's always running to dehumidify the air on rainy or humid days, even when the heat is on.
 

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Discussion Starter · #10 ·
It was occansionally pressed on(digital) by accident. I kept it off but noticed anytime I ran the defrost it would be on automatically. The stuff autozone has on sale right now in my area has two cans the tube with gauage and the refill kit contains a strop leak.
 

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In looking at ALL the hoses, end connectors, fittings, compressor, etc do you see ANY oil residue or other evidence of something other than smooth metal, rubber? That is the first thing you look for if you think your system is leaking. The oil will come out with the 134A and leave a residue film and then it will attract dirt.
 

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But I have to recommend not simply throwing cans of refrigerant at a leaky system, because in the long run you're going to spend more than paying a professional to find the leak.

In the wintertime, were you running with the AC button pressed OFF? If not, then the compressor was trying to run whenever the temp was above 34-35 degrees. Just intermittently, but in our vehicles, it's always running to dehumidify the air on rainy or humid days, even when the heat is on.
Guess I am a little confused with your response...

Are you saying that in the winter time, when running heat, the A/C should be off?

I am fairly unfamiliar with GM products, and just bought my first GM in Feb 2009. I bought a 2004 Rainier AWD I-6 with 56k. It's in great shape and got it for a steal. I am noticing the air blows cool, but not cold. The driver side is slightly warmer than the passenger. Should I disconnect the battery or pull a fuse to reset it? If so, what and where is the fuse to pull?

I swear I love this website..have learned more about cars than I ever planned to. :thx
 

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:iagree: is the a/c button supposed to be lit (on) when in heat? Why do I feel like I'll be seeing Garfield shortly?:bonk:
 

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Discussion Starter · #14 ·
***Important Update***
So today here in central Ohio it hit 85 degrees. So I broke down and went to the Advanced Auto locally and puchased a refill kit with gauge. I follow the instructions and the intial preasure was 15 I brought it up to 45 where it should be occuding to can following directions with the car running and A/C on. I here the compressor kick on. I think yes problem solved well...The compressor will only stay on a couple seconds at a time then kicks back off it continually does this unless I turn the A/C off. So my question now is what the he** is wrong with this thing. The compressor wont stay on so I don't know whats going on. So once again HELP!

Thanks so very much for any help given.
 

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short cycling usually means low refrigerant. Sometimes the little gauges with kits are off a little. I charge systems until comp. stays on continuously. Keep in mind I have never messed with ours yet but suppose all are alike.
 

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short cycling usually means low refrigerant. Sometimes the little gauges with kits are off a little. I charge systems until comp. stays on continuously. Keep in mind I have never messed with ours yet but suppose all are alike.
A lot depends on the ambient temp. At 70 degrees F. it is normal for it to cycle some. At or near 100 degrees, it should not do "short cycling" especially at idle. Usually there is a chart for what the pressure just be at various ambient temps.

I have also seen low pressure switches be bad, in that they would kick off the compressor clutch BEFORE the system actually reached the correct pressure. On some systems (mine in particular) it is usually somewhere around or just under 25 psi.
 

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:iagree: There is a way to bypass the switch to see if this is the problem, afraid to try to explain as you may do more damage to it. Also, he did say it was 85 degrees which would make it to be around 45-50. Old school techs like me sometimes tweak the numbers.
 

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Discussion Starter · #18 ·
I noticed that when the compressor does kick on the pressure drops to 15 to 20. Then the compressor kicks back off. So the pressure drops compressor thinks the pressure is to low and kicks back off so I should just keep adding till it stays on? Or should I replace the low cycle switch?
 

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Different systems use different low pressures on the low side when running. It should lock on around 25 lbs on the low side running. However much above 30-35 low, running, may over charge the system and that is really bad. Do you know anybody with a regular gauge set to check the high/low sides?
 
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