AC Compressor won't turn on
Hey all. I'm having some AC issues with my 9-3. Up until a week ago, my AC was flawless and
extremely cold, then last week, it just stopped coming on. The AC button LED still lights, but there is
no increased work on the engine and the compressor never engages. I've checked all fuses (even ones
not remotely related just to err on the side of caution) they're all fine. The cabin fan still works on all
speeds, so no issues there. The belt appears fine, no tearing or obvious wear.
It's interesting to note that the cabin recirculation button doesn't seem to work either. Its LED lights
up as well, but i don't hear the *flap* sound when the air changes. Any ideas where i can start for a
There weren't any little kids screwin' around with the controls? adults only accessed this control panel? 'cause those little buggers can play hell once they see buttons to press and levers to move, it's all a big playset for these youngsters....not to blame them but could be the controls are comprimized and not engaging~
haha! I wish it was kids. Sadly, this is an adult(ish) owned vehicle without any kiddos to factor in. Would it be worth it to remove the AC control panel and clean out the connector/reseat it?
if you can get to the backside easily am quite certain these are not "soft" interface, knowing SAAB, like MINI use reliable mechanical stuff instead of soft rice interface~yuk, (my wife's prius, get a barfbag) and so perhaps you can see physically a lever's arm moving the control lever and see whether it's doing exactly what it's supposed to. This is my first guess, we will move on is all is righteous in the land of the righteous~
There is a clutch on the front of the compressor that will enable when it is given 12 Volts...you could pluck the connector and see if it IS issuing the 12 volts would mean a defective compressor unit~
of course the car must be on, and the lug is dangerous to measure at that location, so if you could fashion a pigtail out of piece of old wire to get your hands away, but we need it asking for compressor to check whether it's being a bad boy and not co-operating~
if it's not getting the 12Volts, I'm going to research you fuse panel so we know what we are looking at here~
Thanks so much Judge! One comment on the AC control panel, it's a fully enclosed module with a multi-pin connector. I've had to remove it when adding a bluetooth kit to the head unit. I like your idea of testing the connector to the clutch. I wasn't sure if it was wise to disconnect this while the car is running, but if the compressor isn't turning on anyway, what the hell. I also appreciate the pigtail suggestion. Just eyeballing the space around the connector makes it look like a challenge to get my hands in there, much less a Fluke meter.
Confessin' I cannot find a fuse for air conditioning in the fuse panel...has to be an inline fuse on the pigtail or in a special block...perhaps one of my co-horts will pick up the ball, if you haven't got time I'll pass the ball to someone who knows what they are doing~ alrighty....got to get my mail now~ the image I did find came out blurry as am forced to do some screen shots of these .png files~
Judge, i think i may have shot myself in the foot. I was sittin' in the car after work looking at the AC control panel and figured, why not check the connector now. So i pulled the panel and disconnected the cable while the car was running and the cabin fan was on. The fan immediately shut off and now i can't get it to come back on. I tried restarting the car, jiggling the connector in all manors, nothing. This reminds me a whole lot of a problem i had several years back. Basically the fan quit working no matter what i tried. Turned out the wiring going into the fan speed resister had rusted to the point of not making good contact at all. Though, i don't know how unplugging the control panel would cause this to manifest. At this point, i'm debating whether to just go ahead and start removing the glove box to get to the resistor. Here are a couple pics of the control panel and connector for reference: Connector: http://i17.photobucket.com/albums/b55/SilverStone641/2013-04- 08181250.jpg Control Panel Rear: http://i17.photobucket.com/albums/b55/SilverStone641/2013-04- 08181242.jpg
Nooooo, the thing needed someone's attention, you just happened to be handy...the photobucket actin' like a spitoon for me, should concentrate on tearin' right into that, a battery drill fitted with a No.2 phillips or switched out to a 5mm whatever is needed will make quick work of it. Go for it, don't take pictures, you don't have time for that~ the resistor is an ugly caterpillar from hell lookin' thing, you can't miss it-
Did you trip the mains?
That's a really good question and i feel stupid for not checking it already. Let me run outside and check!
You know it's right impossible to find a public domain SAAB schematic for your vehicle...try looking in the owner's manual to find perhaps the location of the fuse for the A/C...we mustn't overlook resources that we may have at hand~
it it sunny by you? cold night last night in central california, supposed to get like summer conditions with the H settin' in- are you in Tennessee or someplace where it's already gettin' dark?
Well, i checked the fuses again. All are intact. There's an AC compressor relay, but it's solid and i'm unsure how to check them, short of replacing them completely. I'm in Texas, it's already dark out. Plus it sounds like a storm is rolling in. As much as i wanna get at it, i think it's best to hold off. Looks like another toasty ride to work tomorrow :(
Sometimes you can use another relay from your PDC, Power Distribution Center aka under hood fuse box. Swap a relay with the same capacities ans as long as it stays running swap them for a minute and see what happens
trying to find what relay does what. click to enlagge
This is the relay i thought about replacing in the engine bay
Go ahead and replace it. Can't do any harm other than your wallet. The only problem is that it's an electrical component and if that turns out to not be the problem you can not return it.
...lookout, H25 at the helm...
Okay gents. So i went home on lunch break and took out the glove box and related paneling and found the loose connection that cause my fan to quit working. So that part at least is back up and running. The engine was still too warm from the ride home to reach down for the compressor clutch connector. I figure i'll put a Fluke meter on it once i get home.
Well, I finally put a Fluke meter on the compressor connector. It started at 0.0V/DC with the AC button off and 0.1V/DC with the button activated. Good news right? Also in the good news category, the horn in the 9-3 shares the same relay as the AC compressor, so i swapped the two. The horn still worked with the AC relay and the AC did not work with the horn relay. I wanna believe this is good news cause it sounds like my compressor is okay, but now i dunno what to check next!
if you want to save money, spend an afternoon at the pickNpull and decimate the donor vehicle of all electrical parts, they give you a grocery bag of them for thirty bucks~
My first thought when something like this happens is to check the compressor. Does your fan function okay? Have you checked your lines to make sure you don't have a leak?
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