I have a 99 Forester L 5spd. The A/C seems to have stopped working, but it happened gradually, over the course of about 3 weeks. At first, it refused to work maybe 1 out of every 5 times the car was driven; the other 4 times it worked fine. The frequency of non-operation steadily increased until now, when it doesn't work at all. It really seemed to be a binary distinction: either it worked, or it didn't, but the air it output didn't seem to be less cool when it was working.

 

As you would expect, this happened about 200mi past the extended warranty expiration.

 

Other relevant info:

In the 2 months before this happened, I drove the car on two 4+ hour highway trips when the A/C was on almost the entire time, so it got a couple of big workouts.

 

The A/C fuse is OK.

 

When I push the A/C button, the idle increases and the second fan kicks in, but I don't hear the characteristic "whoosh," which I'm guessing is associated with the compressor clutch engaging.

 

 

Any troubleshooting advice would be appreciated. I really know zilch about A/C, not even how to check the refrigerant level.

I'd suggest taking it somewhere. It probably needs to be charged up, and if you don't have the background, gauges, etc. You're better off taking it somewhere to have it looked at. Most places will do a diagnostic for 20 bucks or something like that. Even if you don't want them to do the work, however some may put that 20 bucks towards the work if you decide to have it done by them.

 

Ask around for some good local a/c shops.

Josh, I was about to take it in when I tried one last thing that was within my technological limits: turns out it was a bad relay. It looked OK when I initially pulled it and popped the cap off, but turns out it wasn't working at all. After swapping it with the horn relay, A/C worked fine, but no horn!

 

The mode of failure makes more sense now: relays either work or they don't, but they can go bad gradually.

 

I hate to pay $40 for something the size of a piece of bubble gum, but it's about the cheapest solution there could have been.

sounds like a pretty cheap fix in the big scheme of things.

If the relay is pulling the contacts down (clicking), take it apart and clean the contacts. They just get arced up a bit.

 

This way you'll have a spare.

 

Tiny