2002 L100 - AC - Blows Warm Air

[bhoard]

My 2002 L100 blows hot air when the AC is engaged. I do not hear the AC compressor clutch engage when I toggle the AC on or off, and the engine idle remains pretty static. If anything, it might idle 100-150rpm higher with the AC "engaged". Again, the blower is moving hot air, and I don't hear the compressor clutch engage.

This afternoon, I checked the 10A A/C fuse under the hood, and that looked fine. I swapped the A/C relay with the relay for the horn (same relay type, and I know the horn relay works), and got no change. I did note that under the hood, there was an air solenoid 10A fuse that was pulled, and I replaced that with one of the spares. This particular 10A plug is just above the 10A A/C fuse. Again, that gave no change. I still do not hear the compressor clutch engage.

The A/C button in the cab lights and toggles on and off, so I don't think the button is bad.

The 30A main A/C fuse drives some other systems that I know are OK.

What else should I investigate?

These cars use a serpentine belt, so its not a matter of the belt slipping or some such, right? I would probably hear the slipping if it was.

Thanks in advance!

[fdryer]

Unfortunately, you are going into the summer season with no a/c until you can fully assess the situation. With all the ground work done comes the reality of this situation - you and many others will find out the main cause of a/c issues comes from a LEAK that has occurred and the system will protect itself from compressor damage by disabling power to the clutch coil. Don't presume to bypass this feature as you'll most likely damage the compressor. You can find the bypass procedure easily if you insist by searching around here. Once you are convinced a refill will work is when you begin chasing an expensive repair, starting with the refill cans.

Find the source of the leak first and determine whether you're capable of repairing or replacing parts and/or if you wish to have all/most/some of the technical a/c work done by a professional shop. There are no short cuts with refill cans if a leak is never accepted or acknowledged because every a/c system is sealed and under pressure when it was operating. Any leak will release R134a/dye/oil at the source and mark it. A leak is not an excuse to refill with store cans as it can just as easily leak out the same place. Avoid leak sealer unless you are prepared to hand over your wallet to any shop just waiting for this type if mistake - they tend to make more money from DIY/amateur mistakes. A/C repairs can get complicated very quickly before you know it.

In addition to simply looking everywhere for dye (greenish yellow) and oil marking the spot of a leak, you may need some basic inflrmation; http://www.saturnfans.com/forums/showthread.php?t=80107

And if you're mildly interested, less than a handful of members here have successfully repaired their a/c systems while the rest were never heard from again. Those successfull repairs resulted in major effort to fully understand and use all the equipment required for airconditioning repairs. No short cuts are possible despite many attempts at it, all starting with a refill can.