We have an 03 trailblazer. Its the wife's daily driver. Suddenly the A/C quit.After it has been sitting awhile , like over night you start it and the A/C will work for about1/2 hr. then it shuts off. the blower works but its hot air.The system is charged changed the orifice filter. low pressure switch is good. What am I missing. Thanks

 

We found out by opening a window after the A/C stops blowing cold the A/C starts again. It dose this all the time I figure there must be a short or bad ground somewhere. So for now when the A/C quits I just bump the window down and right back up and its good again for awhile.

 

That has to be one of the top weird things about A/C that I have heard of. Has to be in the module or electricals/sensors for sure.

 

I was thinking the module too but wanted in put guess I'll be changing that Thanks

 

Changed controller in dash. No change. Hot wired compressor but clutch wouldn't come in. It ran intermittently and got cold but only when it wanted to. Bit the bullet and replaced the compressor BINGO we now have air when we want it.

Thanks for all the help
Charlie

 

Well at 16 years old that's a good run on the compressor. Nothing lasts forever, not even us. :-)

 

Yes but the most fun was figuring out what was wrong. Now the wife is happy which makes me happy. Thanks for all the help

 

I'm going to take an internet car expert guess and say there was nothing wrong with the compressor. You were low on refrigerant. Been there. Done that and I'm MVAC / EPA 609 as well as EPA 608 Universally certified. My truck always cooled perfectly then stopped. Low/High side was within theoretical limits but wouldn't cool unless cold out or highway speed when under 80 F. Checked everything and all was fine. Finally, I evacuated and pulled a vacuum. Vacuum wouldn't hold. Leak in coil. Replaced coil, pulled vacuum, held no problem. Charged with measured amount and ice cold every since.

I'm also the original owner of the truck and nobody has ever touch it mechanically but me, ever.

 

NOPE System was drained recharged several times while checking switches and lines and filter. It was charged. It just worked when it felt like it The compressor has been in now about a week or more and have had no problems since.

 

Check grounding wire G108 located behind alternator on block. I was having the same problem, this is a 10mm bolt be careful not to over tighten and break it off. Clean the wires and replace bolt.