It seems that every year, my A/C stops working. I have been able to fix it in the past but now I am stumped. All the hoses and tubes are new as of last year. The compressor kicks on and immediately back off. My uncle hooked his gauges up to it and put a can of freon in it. We then discovered that the line going into the evap core is cold, but not coming out. The reason I don't think the core is the culprit is b/c the pressure is not building as if it were blocked. Any suggestions on what to try next?


2001 Silverado 1500 LS Z71

 

On the accumulator, there is a low pressure switch/plug. Pull that plug out and jump it with a paper clip in each side. If the compressor kicks on, then the switch is bad. They're stupid easy to replace. You can get a good grip and turn it off by hand. When replacing it, hand tighten it then tighten it 1/4 of a turn more and thats it. On the switch itself(accumulator side) there is a rubber band on it. That rubber band is important cause you'll need to get the same colored one when you replace it. Has to do with the pressure it reads.

 

Thats one of the things I am gonna check today. I had to replace that switch a few years back so I know the procedure. Back then though the AC would work for 10 minutes and then cut out. That's why I was a little hesitant to try that first.

 

Went ahead and replaced the pressure switch. There is no change. Any other ideas?

 

If the compressor is short cycling on off on off fast then you have a low charge