A/C Compressor Question

[DSM_23]

Im pretty sure my a/c compressor is not kicking on when i press my a/c button. When i push it, it will turn on the a/c fan but i dont hear the compressor click on like before theres no cold air, and i dont see the idle go down much. Is there a fuse for the compressor or a relay i could possibly check, whats the deal?

justin

 

[Hottalon92]

shit I'm having the problem It got hot here today and I tried to turn on my air cond and nothing? can anyone help.

 

[XtrapspeedX]

i have the same problem.

 

[realhp=turbo]

Yes gentle men I think I can cast alittle light on the subject for you. To answer the origanal question , yes, theres an entire relay box dedicated to the A/C system aswell as various other fuses in other boxes. The A/C relay box is located (in most 1g's) under the hood, up by the firewall on the drivers side. There is a fuse for the A/C in every fuse box you find so check them all. even the relays on the battery. If all those work then youve got a charge problem. Question; Did you know that when you turn on your def your A/C pump kicks on? Even in the winter. It does that to literally suck the moisture out of the air in the cabin. Also in effect keeping your A/C system functioning during long periods of non-use. If you for some reason have lost your charge, know this. R-12 is not produced any more. In 1994 FDA and the EPA passed a law that required all car manufacture (ers) must switch to R-134a. Less harmful to the ozone. what this means to you is R-12 is still avalible but it costs 60bucks per pound. Your average car A/C system runs 2 lbs.
R-134a, however, is half that. Typically, 134a goes for $35 per/lb.
mike

 

[DSM_23]

Are you sure theres a fuse for the a/c in every fuse box, that being both under the hood and under the dash? Also where are these relays on the battery? Yes i did know that the compressor kicks on with the defroster, and i know i have charge becuase ive used it not to long ago, but now i figured i may have blown a fuse or something

justin

 

[realhp=turbo]

Yeah dude, Im pretty sure that there is a fuse for the a/c in every box. But there isnt a box thats so well hidden that you cant find it, if that makes you feel better. You might also try checking to see if the a/c clutch acuator wire is still attached to the compressor. That might also cause this problem.

 

[DSM_23]

By referring to the wire attached to the compressor are you referring to the connector right on top by the low pressure valve. Because that connector is connected all thats been checked, i just didnt know if maybe there was a fuse or main relay that controlled the compressor by itself or not.

 

[realhp=turbo]

Yes that was exactly what I was talking about. And yes there is a fuse and a relay that help operate that thing. And I do belive that they are in the box that is closest to the driver, under the hood on the firewall. Try that one.

 

[DSM_23]

Alrite now, I'll see if that works tmw, thanks for your help.

justin

 

[Attack Eagle]

I did not see it clearly stated previously so I'll add this.

There is usually a pressure switch in one of the lines (I don't remember which one) that will open when you don't have enough refrigerant in the system and will keep the compressor from coming on. It's there to prevent the compressor from being damaged due to oilstarvation so don't bypass it except maybe to see if it is the switch and only for less than a second. If so head to your local shop for testing and possible recharge. (note very very infrequently the switch/sensor will go bad but you need to make sure you have a good charge before bypassing it. Even better have them suck out the refrigerant, replace the switch and then put the refrigerant back in.)

BEst of luck to all of you!

 

[4G63dsmpwr]

Well I'm having problems with my AC system as well. All my fuses are good, I have about 60PSI of pressure of fresh R134 freeon. No leaks, been holding 60PSI for about 4 days straight. The connector on top near the low pressure fitting is connected, no problems there.

My compressor just never kicks in though. Any ideas why this might be happening? How do you bypass the switch, witch when it realizes 45PSI of pressure, or whatever it is on our cars - it kicks it on. I'd like to try to bypass this if possible, because I can't figure out what else it could be.

Thanks for the space!

 

[realhp=turbo]

I hate to tell you this but there is no a/c system in the world that runs more than 3 to 4 lbs per sq inch. Your system in a 90 (unless it has been converted already) runs R12 at 2 lbs. I know this because Ive worked in the feild and am a/c certified. Try checking to see if the electic clutch on the pump is plugged in. It would be the only wire that runs to the pump and is located very close to the pulley/clutch. If that doesnt fix the problem ask me again.

 

[4G63dsmpwr]

I converted the system over to R134A. I did the conversion with the fittings and everything. It has a guage on the end, and it says that between 35-45 is "full" and mine sits at 60, so its actually got too much pressure I think.

I have already checked that wire right on top of the compressor, and everything is onnected correctly and looks fine. As mentioned previously, I've already checked all the fuses as well.

I just realized this: the car I recently bought does not have the ac fan -- would this cause this problem? I mentioned this before in another post, and somene said I can run a 12V line right to that wire. Is this safe and everything? And what wire would I run the 12V line too?

Thanks for all the help!

 

[mmughal]

Guys,
A/C works fine. Cools fine also, but sometimes, while am driving with A/C on Compressor doesn't turn back on then i have to drive withouth A/C for few min switch it off and it comes back on sometimes and sometimes it doens't. Can anyone help
tell me what needs to be checked.

Regards

Mansoor

 

[Defiant]

Guys,
A/C works fine. Cools fine also, but sometimes, while am driving with A/C on Compressor doesn't turn back on then i have to drive withouth A/C for few min switch it off and it comes back on sometimes and sometimes it doens't. Can anyone help
tell me what needs to be checked.

Sounds like your refrigerant is low in the system. Check for leaks and re-charge.

 

[Syndicate]

a/c ? figure this one out .. my car surges and loses power on and off when i turn on the a/c .. so bad you can feel the car jerk back and forth .. its a new compressor r134a or whatever i filled it full of new freon and it still does not get cold at all.