A/C won't work

In my 98 Blazer, the a/c won't work any more. I still have everything else (heat, etc...) but when the a/c button is pressed the compressor never turns on. I replaced the climate control inside the car because it didn't light up the whole face anymore. I assumed that it shorted out and the whole control unit wasn't working correctly (still had heat and other controls just not a/c). Anyways, I'm back to where I started with a new climate control but still no a/c. I checked all the fuses and even bypassed the fuse to the compressor and managed to turn the compressor on (still would not blow cold air). I also bypassed the sensor that runs into the metal canister on the passenger side (don't know the name). It also turned the compressor without cold air blowing.


So what's the deal, is there another sensor that I should check? I don't have a wire diagram so I don't know if theres something right after the a/c button that's not completing the circuit. I don't know if it's because I have the "special a/c unit" with the auto controls that might be adding to the problem or what... :disappoin

Any help would be great, considering I'm running out of ideas.




thanks
fred

You might be low on refridgerant

I didn't check the pressure but when I did push the valve in, it did blow out coolant. Would that actually stop the compressor from turning over when I push the a/c button? I will check it again since I do have a recharge kit if it's low.



thanks
fred

I didn't check the pressure but when I did push the valve in, it did blow out coolant. Would that actually stop the compressor from turning over when I push the a/c button? I will check it again since I do have a recharge kit if it's low.



thanks
fred

Low pressure switch will prevent the compressor from engaging if the low side pressure is below a preset value...usually around 25 psi

Had the same problem with my 95 blazer. Went to Pepboys and bought a can or R-134a with a hose already connected to it for $12 and put it in (follow instructions on can). You put the refrigerant in as the truck is running with the AC ON and as I was doing this, the condensor turned on and stayed on. Cold Air just as new for $12!

Hey thanks for the help, I just added some R134a and found where it was leaking. I might of fixed the leak but I won't know for sure till a few days. Thanks again.




fred