My A/C worked flawlessly for the first two summers I owned the truck, now it freezes up and quits blowing, If i turn off the compressor off and leave the fan on high it will thaw and work for a while then freeze up again. Also having troulble with the passenger vent not blowing cold. I checked the freon levels and the pressures were right on. Any ideas, Any one else having the same problem?

 

There is a TSB on this issue. It is the fin temp sensor relocation for the evaporator. They are moving the sensor to the coldest part of the evap. so the compressor shuts off quicker to ensure the evap. dosen't freeze up. Reference the Thread about the 03 A/C issue.

 

I had the same problem but it turned to be leaking o-ring at firewall and low freon. I have also read about the fin / temp relocation --but after a re-charge it was fine ?

 

I would try to put just a little bit more freon in the system. Your pressures can be accurate according to a book, but not actually work in fact. If you checked it idling, it may have read right, but driving down the road you are moving more air through the condenser. That would lower your pressures just enough things might freeze. I have this problem here in Iraq, except our problems are magnified alot. I am seeing temps in excess of 150 degrees. I have to run my systems about 60 pounds higher than the book to get them to work. This wouldn't be a good reference for you, but just to show you, I am running about 490 pounds on the high side. I have a different type of system than a regular R-134 auto system. I would try adding about 1/4 of a bottle (small) of freon from an auto parts store. Try that, and if it doesn't improve after the whole bottle is in, then look elsewhere. If that doesn't work, pm me and I can get you some more solutions.

 

My truck did the same ting, but only where the humidity was high. It sucked driving through Texas in the summer with no A/C! I took the truck in and the dealership said nothing wrong with it. They didn't mention any temp sensor. Just said it was low on freon...even though I told them it was blowing ice cold after Is hut it down for an hour or so.