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Discussion Starter · #1 ·
Been a long time since I've looked at the site - very impressed!

Anyway I have a problem that maybe very simple to work out -

The other day when the weather was hot I was stationary with the engine running and all of a sudden there was a loud pop from under the bonnet followed what appeared to be mist coming out under pressure. I stopped the engine & had a look under the bonnet and found some residue on the fan and top hose (bit like silicon grease spray) - I assumed it could have come from the air con. Air con / econ works fine but when I went to pick up my partner and new baby from hospital I couldn't change the heat setting unless the ACC runs on Hi - then its hot! Or too cold for the little fella - had a look under the bonnet again because I could hear some slight hissing and found a little rubber hose had blown off the top of the engine (LHS) - reconnected - no hiss - no warm air only cold or hot. Actually also noticed that the car stalled a few times since that little hose came off?!

Any ideas would be gratefully received so my new little boy can travel in comfort at the right temperature without arctic or sahara side effects!

9000 CSE 2.0 LPT 94 M

Cheers
 

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Sounds very similar to what happened to me...
Only you forgot to mention the [expletive deleted] like smell of that...
As well the dumped fluid may be in bright-green color if the fluorescent freon oil is used in ACC.

Ok, I had made post or reply on similar theme about month ago (when it happened to me).

The possible cause is failed ACC pressure sensor. Which, if failed is not starting ventilator at the right moment (when the ACC contur gets over-heated/over-pressurized). Thus ACC is forced to dump excess pressure through the dump valve on back of ACC compressor.

The temporary solution is to uncover the ventilator relay and block it in closed position every time you drive...

The pressure-sensor by iself is much like the main temp sensor (on radiator), but this one is located on freon accumulator downwards the right wing.

BR
Dzintars 9000CS23T
 

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Discussion Starter · #3 ·
Thanks for the advice - sounds a good possibility. One more question though, would that stop the heater working through the range of temperatures? Doesn't matter whether it is set on 17 or 27 the temperature remains the same, Lo works fine and so does Hi - plus there is no difference as to whether I use Econ or Auto.

Help!
 

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Discussion Starter · #5 ·
Thanks Paul I am chuffed to pieces! A future Saab nut I hope.

Further idea on the heater problem - does anybody think that it could be caused by a vacuum leak somewhere? I am still trying to get my head around why I have cold and hot but no in between.

Another dumb theory - don't suppose that whilst the weather is warm the ACC automatically decides that I am stupid for wanting any temperature other than cold and therefore overides the 17 - 27 heat settings and just gives me cool. Could someone do me a favour and try their ACC and let me know if they get different heat through the range.

Any ideas would be handy - this is driving me mad because I just can't see the logic!

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Irrespective of whether the ACC is set to AUTO or ECON the temperature is regulated by the ACC system adjusting the mixer flap with a stepper motor. It measures the cabin temperature, the temperature of the outside air, the mixed air and the amount of sunlight and adjusts the mix to achieve the desired temperature. When on Auto the air conditioning compressor is activated and isn't on ECON. The system will also adust the fan rate to achieve the set temperature more quickly. Pressing any of the other buttons to direct air to different vents or alter the speed puts it into "Manual" and stops the automatic functions.
In your case it looks like the mixer flap is either fully at the cold end or fully at the hot end. Could be a faulty stepper motor or it could be getting a duff signal from the electronics.
Check out http://216.78.172.244/climate_control_fold...ntrol_docs.html
 

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Discussion Starter · #7 ·
Cheers for the site information Derek, will have a look tonight and see what I can do. I think you may be right about the sensor because it does seem to be stuck (probably) around 18 C

Hopefully my old meter will give accurate enough readings to get me closer to a solution.

Will keep you posted
 

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Discussion Starter · #8 ·
Next update -

checked all sensors and all appear to be working ok, cleaned all connectors and checked that they seat ok - no problems and still no mid temperature.

However came to work this morning (had a play with the temperature controls as usual) and blow me the damn thing works!! Could be a faulty connector - will continue tests and let you know
 
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