A/C or ECC System Not Functioning - 97' 850 GLT

[bpwsource]

Hello all you Volvo masters!

I have some questions...about my faulty A/C system. It's not working. How do I fix it?!

Ok, ok...to be more specific, it has been (as far as I can remember) cycling on and off, or rather randomly switching between Cold and Hot air for the past month. Most of the time the A/C worked fine. Then I took a 700 mile roadtrip with ambient temperatures ranging from 85-100 degrees. During the first part of the roadtrip, the A/C worked fine. It was during the the 700 mile drive home when it failed to function properly. No switching on and off, no cold air, nothing.

My system will blow Hot air if I turn the Heat up but when I switch the ECC system to Full Blower, A/C and Max Cold just warm air comes out.

Now, I have done some research and know it can be a number of things....Compressor, Compressor Clutch, Clutch Gap, Evaporator, Dryer, Condenser, Relay Switch, etc. etc. etc. SO, my question for all of you is: "How do I know WHAT is causing the problem??"

Oh wait...I DID test the Low Pressure Port in an attempt to "recharge" the system with some r134a freon. I turned the Engine on, put the ECC system on full A/C and plugged the tube/gauge into my Low Pressure valve. I was expecting (hoping) the PSI to be around 20-30 and then I would just fill the system back up to 40-50 and be on my way. However, the gauge read 95 psi - well into the RED. What does this mean???? Clog? If so, where? And how do I unclog it? Should I really go get a High Pressure Gauge kit to test that as well? If so, where is the High Pressure valve located?

Also, in your advice, pictures would be heavenly. I don't even know where my compressor is or what it looks like let alone anything else (except the low port valve). I do have a Haynes manual - does this have pictures of all the components?

I would really like to keep this a DIY joy for I am a Grad Student - enough said...


Thank you Volvo masters, ahead of time, for all your patience, assistance and wisdom during this repair process. I promise I am component enough to fix many car-related issues. I did spend an entire day replacing the Blower, which is located behind the passenger air-bag, about a year ago. And that is working fine now.

PS... Also, could it just be a faulty switch or relay? If so, how do I test that? I read posts talking about "jumping" or "bypassing" the relay, switch or sensor but I have NO CLUE what that entails...



THANK YOU!!

Brian



ALSO... I am listing this issue here as well because perhaps they're all connected?? My ABS and TRAC service lights are frequently on. Not all the time - usually after I've been driving for a bit. Also, when I press the TRAC button (right next to my sunroof button) the light doesn't go like it supposed to... But it will come on all by itself along with the ABS light. Much more rarely (maybe once every 2 months) my Winter Traction Mode (the Up Arrow Light) will just switch on by itself and I'll be stuck in that Transmission mode unless I turn the engine off and back on again. These two issues have only been a little annoying but have not affected the Function of the car in any way...yet. Does this mean my Traction Control and ABS system need to be repaired? Or they have faulty sensors? Etc? Ai yai, yai...

**UPDATE: AND... I just did a check a friend recommended to me. I think I found the compressor, by the way. I traced the low port line to a Cylinder (which I am guessing is the Dryer?) and then the line that comes out of that to a horizontal cylinder attached to the Serpentine Belt...I am guessing this is the Compressor? Anyways, the Test. I turned my heat on full blast and turned the engine on. I checked the compressor and the belt/wheel were spinning (does mean it was on?). Then I changed my ECC controls so the A/C was on Full (of course no cold air). My friend told me to listen for an audible change in the Engine sound - the compressor turning on and pulling power from the engine. No change. I don't think. At least nothing significant. And the wheel/Belt was still spinning around what I think is the Compressor. What I DID notice, however, was that my Radiator Fan was not spinning either time - Heat on Full vs. AC on Full. I did just turn on the car...ambient temp is about 76 degrees and sunny. Is this normal or could the problem be my Fan? Ugh...the Rabbit Hole gets deeper.

[bpwsource]

UPDATE #2: I went back outside to take some pictures of the engine and specific components in hopes some of you could tell me what I'm looking at. I also took a better look at what I'm pretty sure is the Compressor and noticed that, although the Wheel/Belt are spinning, it doesn't look like the actual compressor is engaged/turned on. I noticed a very thin disk (is this the clutch?) that is on the outside of the Serpentine Wheel on the Compressor which is not spinning at all. It didnt spin when the Heat was on Full blast nor when the AC controls were on Full blast. And the radiator fan was still not spinning (not sure if this just cycles on at certain times or not...)

Also, attached you'll see pics of my r134a bottle/gauge with the PSI reading of almost 100. Not sure what this means. Could this be caused by the compressor not pumping? If the compressor isn't engaging, what does this mean? Clutch? Relay? Faulty Compressor? How do I know what is the actual cause of the compressor not starting?

Thanks!

[jblackburn]

First of all, welcome to the site! I'm glad to see that you're definitely one to do your research about things, before asking "my AC doesn't work? What's wrong with it?". We like that

The pressure in the system is so high because the compressor itself is not running. You are right on with your diagnosis - it sounds like the clutch is not coming into contact with the compressor itself.

Here's cheap, easy fix for that:
http://volvospeed.com/vs_forum/index.ph ... h-gap-fix/

I did this on a friend's V70 about a year ago, and it's still working great.

Once you get that running, take a look at the pressure with the compressor running. There is a diagram on the back of the can for typical pressures in correlation to the outside temperatures.

The ABS module is a common failure on all 96 and newer models that nearly all of us have dealt with. If you're any good with a soldering gun, it's a very easy fix:
https://www.matthewsvolvosite.com/forums ... hp?p=46827

If not, you can pull out the module and send it off to Module Masters or Vic Rocha (google either of them) and have a replacement sent back your way in days. In the meantime, you won't have a speedometer, though, but the car will still drive OK (most GPS units will tell you your speed if you've got one).

Pretty car though...I understand the whole grad student part and not having money, as I'm one myself (well, part-time ) Take some Armor All or a product called "Black Again" to the plastic on your bumpers/doors, and it will make a world of difference. For a more permanent solution, a heat gun to the plastic actually brings back its color.

[JRL]

Do NOT use Armorall or Black Again
Armorall is not designed for this and will wash right off, Black Again os the worst of the black products and (again) will start to wash off and streak in a rain or two.
If you want to use a black restore product, FOREVER BLACK is the best and it lasts. It takes a little longer to apply but will not wash off.

If you want to take a Saturday afternon, paint all the moldings and that's permanent
You can buy a couple of spray cans of gray/black bumper paint at any automotive store.
The most of youe time will be spent on carefully masking everything, your actual paint time shouldn't be more than 20 minutes
If you decide to paint, come back and I or someone will tell you how to prep the moldings

[bpwsource]

Thank you thank you thank you. I am going to attempt the clutch/compressor fix tomorrow. I just bought (and now will return) an OBDII scanner to search for DTCs - 0 codes found... There's obviously something wrong with both the AC and the ABS module so why doesn't it post at fault codes?

Anyways, thank you again for your assistance. I hope this will work. Pictures and updates to come!! As a celebration and gift to my car once the AC starts working ill probably paint the molding and bumpers like you both mentioned. JRL, I would love some instructions in how to carefully prep the car.

Thanks to both of you again! Again, updates to come!

[bpwsource]

Update: I'm just curious... how do I know the clutch bread clip it reshim will work? I tried the broom handle test biting used a hard plastic snow/ice scraper and nothing engaged. Although I'm not quite sure what the clutch is or what I should be pushing on or tapping... is it just the outside of the wheel attached to the compressor? When I pressed it in it made some sound but I think it was just the sound of the part I was pressing against rubbing against the spinning wheel.. any suggestions?

Thanks!

[jblackburn]

Ok, test #2. Before you try that gap fix, find a paperclip or something to jumper this switch with:

Make sure the AC is switched on inside the car, then pull off the plug, and short the terminals (BRIEFLY). Does the compressor click on?

If it runs, hook up your gauge and then short it again until it pulls the pressure down. What are you seeing now?

[bpwsource]

Ok jablackburn,

Wow. I did it. I used a paperclip to "jump" the switch you have pictured. The compressor started up! I plugged my gauge in and did it again. The pressure then fell from 90ish to around 10 psi! So...assuming this was the next step (hopefully), I went ahead and added the r134a until the psi read and stabilized around 35psi which matched the ambient temp settings on the bottle.

Then I plugged the clip back in, detached the gauge and waited but the compressor did not engage by itself. Does this mean the switch/sensor is busted? If so, is it an easy fix?

Wow...I feel a lot closer to fixing this now! Money spent thus far... $0.00!

Alright...Next Step?

[jblackburn]

Well, you've found it. But looking at it, I'm pretty sure that means evacuating the system, installing a new switch there, and then refilling it. All the refrigerant will shoot out as soon as you unscrew it...you'll have to get a shop to do this; otherwise air will get in the system.

[bpwsource]

Ooo... hmm. Ok. Now for the million dollar question... How much do you think this will run me?

- So, if I were to unscrew that switch myself all the refrigerant would should out? How does a shop do it?

Thanks again for all your help. Sure its not the $0.00 answer I had hoped for but at least I know what's up now.