Last summer A/C worked fine. This summer not blowing cold air and I can see that the compressor is not turning on. I swapped the relay with some of the other fan relays and no change so I think the relay is fine.

 

I also ran the self-diagnostics and it showed everything fine.

 

What is the next step up the ladder? Recharge? If there is a leak will this disable the compressor from turning on?

 

Thanks in advance.

There is a known issue with the compressor rotation sensor on those.

From what i read if that rev sensor is bad than the compressor will run for 30 secs or so before turning off the compressor. Since mine isn't turning on at all could the problem be elsewhere in the system? Anyone have any insight on the rev sensor on these?

low refrigerant pressure will shut it off.

 

gaugeswould confirm that - dunno if the self diagnostic would. maybe the low pressure sensor is bad?

It is most likely simply low on refrigerant, my 03 H6 needed a can at 160,000 or so. If it doesn't last a season or two I'll chase down where the leak is.

 

It could be other problems, such as the rev sensor or even the clutch itself.

 

First step is to get a gauge on the low-pressure side, I have to imagine you could get a garage to just check that and then do nothing more for not much money.

 

If it has enough pressure that it should be running, try pressing on the A/C clutch/pulley with a stick of wood, try to force the plates together. If it runs when you apply pressure the clutch needs to be maybe cleaned, maybe needs to have a shim removed.

They are also known to leak around the pressure fittings on the hoses. Very common issue that I've seen numerous times. Check the hoses for any oily spots around the fittings and if there is, replace and recharge.

My 02 H6 had a similar issue. Turned out the o ring was bad. Replaced that, recharged and cool air once again.

 

Ahhhhhhhhhhh..........................!

FIRST step is to verify how much, if any, refrigerant is in the system. have you checked it?

the compressor won't come on if there's low pressure. very common.

 

so far i've fixed a number of that era H6 air conditioning systems inexpensively with ease.

 

You may want to read my write up - takes 15 minutes and less than a dollar (not counting the refrigerant):

 

http://www.ultimatesubaru.org/forum/showthread.php?t=132408

You may want to read my write up - takes 15 minutes and less than a dollar (not counting the refrigerant):

 

http://www.ultimatesubaru.org/forum/showthread.php?t=132408

 

Great write up. I'll replace the o-rings this weekend. Thanks!

FIRST step is to verify how much, if any, refrigerant is in the system. have you checked it?

the compressor won't come on if there's low pressure. very common.

 

so far i've fixed a number of that era H6 air conditioning systems inexpensively with ease.

 

You may want to read my write up - takes 15 minutes and less than a dollar (not counting the refrigerant):

 

http://www.ultimatesubaru.org/forum/showthread.php?t=132408

 

Gosh, wished this existed last year when my A/C took a dump on my STi.

Come to think of it, when I bought my '03 H6 used from the dealer they replaced an AC part free because there was a recall. Not sure what part it was.

Great write up. I'll replace the o-rings this weekend. Thanks!

 

if you do this you may release any refrigerant that is in the system. anf if the system is holding pressure then the o-rings are not leaking. so checking the pressure in the system first is not a bad idea. even if you use one of those refill cans that comes with a cheesy gauge.

 

AC folks will fuss if you release that stuff into the atmosphere and also if you refill with out pulling a vacume but such is life.

 

my 01 H6 came with a non-working AC last year (159k miles). i recharged it and got nothing. it turned out my compressor was bad. so i replaced that and recharged it again replacing 0-rings as i went.

 

works great now.