Hello everyone, I recently had my motor replaced in my 04 F150 5.4L Lariat. When spring rolled around my a/c was not working and bought freon assuming mechanic didn't add any back. Well it worked for some weeks then all of a sudden it would stop blowing cold air and blowing hot air. I would turn off "a/c" and a few minutes turn it back on and I have cold air for a few more minutes. This seems to happen on really hot days and I was able to visually check compressor when it stops blowing cold air and noticed the clutch on the compressor is not spinning. Is my compressor bad, clutch and/or freon system needs to be evacuated and recharged? This is my limited experience on trying to figure out how to repair.

any insight on how to diagnose problem would be greatly appreciated.

elijah

 

 

You can check the relay and the diode in the box nrivera has suggested. You can also jump the low pressure switch for a short time just to test and see if the switch might be bad or you might have a leak. You crawl under the truck, with the truck off and apply 12v to the compressor clutch and listen for the clutch to kick in and out. Do it a few times to make sure that it's not sticking. What mine turned out to be was the connection to the clutch. I was getting 12v to the plug going into the clutch but the clutch wasn't engaging. I cleaned both the male and female ends of that plug and even had to slightly ben the little pins on the male end. Plugged it back in and haven't had a problem since.

 

Have the system evacuated, correctly, checked for leaks then recharged with correct amount. See what happens. Could be shutting down for numerous reasons, but first you need to ensure it is correctly charged by weighing back in correct amount.

Also, have the FOV checked while the system is empty, if this system has one.

 

Honestly, with A/C. I'd almost always advise you go to a shop who specializes. Too many little things

 

The small relay on drivers fender is kind of light duty . Mine was intermittent ,was burnt on contacts after 10 years . That solved clutch not coming on but after awhile had to add some Freon to get it colder . But much more than this get a good ac guy .

 

I'm all for DIY. Hell, I re-did my trucks entire A/C when the compressor blew up. You can just cause a lot of damage if you don't know what you're fooling around with.

 

i had a similar problem with my ac cutting in and out, my clutch was starting to wear out and slipping, if you take that small bolt out of the front( 8mm i beleive) your find some thin washers deep inside, take one out and check your clearance, i beleive its supposed to me 40 thousands clearance from the plate to the compressor, i took one out and its been working perfect ever since, takes about 10 minutes to do

 

My similar problem was the clutch coil. That one finally quit this past July... in Dallas... on the way to Austin... at 103°F.