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Hi all, I believe I have this issue. If I remove the sensor and hold it between my fingers to warm it up the compressor kicks in. I've sprayed it with contact cleaner but hasn't made any difference.

Does anyone know where I can see the sensor readings in MES? I think it must be reading much lower than it should and the car thinks it is below zero, but can't find a sensor that looks 'out'?

Has anyone managed to work out if this easy is replaced without a whole loom?

Many thanks, all 👍

View attachment 956125
On climate control live data I think the temp sensor is referred to as evaporator temperature
 

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On climate control live data I think the temp sensor is referred to as evaporator temperature
Thanks. I looked again earlier and can't find that sensor or any others that change when I hold the sensor in my fingers to warm it up.

As a test I have now clipped the sensor out of the way outside of its housing, as whilst on the drive this seemed to make the compressor kick in as it should. As soon as I put it back in its place it seemingly got cold and the compressor cut out 🤷‍♂️
 

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Thanks. I looked again earlier and can't find that sensor or any others that change when I hold the sensor in my fingers to warm it up.

As a test I have now clipped the sensor out of the way outside of its housing, as whilst on the drive this seemed to make the compressor kick in as it should. As soon as I put it back in its place it seemingly got cold and the compressor cut out 🤷‍♂️
Like I said, measure across the terminals of the bit you've now cut off and you should be able to easily replace it. If it's working without it in situ then it's more likely a NTC than not :)
 

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Thanks. I looked again earlier and can't find that sensor or any others that change when I hold the sensor in my fingers to warm it up.

As a test I have now clipped the sensor out of the way outside of its housing, as whilst on the drive this seemed to make the compressor kick in as it should. As soon as I put it back in its place it seemingly got cold and the compressor cut out 🤷‍♂️
have you had pollen filter out and checked it’s not blocked? The temp sensor could be doing what it’s supposed to?
 

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Like I said, measure across the terminals of the bit you've now cut off and you should be able to easily replace it. If it's working without it in situ then it's more likely a NTC than not :)
Thanks for your tips, I will need to get hold of a multimeter. I've not cut anything (yet), just unclipped the sensor from its housing and tucked it out the way outside the housing
 

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have you had pollen filter out and checked it’s not blocked? The temp sensor could be doing what it’s supposed to?
Yes, new filter was the first thing I did when the a/c started playing up. No change and then went for a regas, which also didn't make any improvements
 

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Thanks for your tips, I will need to get hold of a multimeter. I've not cut anything (yet), just unclipped the sensor from its housing and tucked it out the way outside the housing
Mine was just diagnosed as a bad frost sensor. It was fine and i had cold air when i brought it in, but luckily it wasn't working today when I went to get the car, so the fault could be pinpointed. I got a pretty reasonable estimate but the Olympics are delaying all parts deliveries. I love the shop and am thinking of taking out a life insurance policy on the Alfa specialist. Note on Frost sensors: the temperature rarely goes lower than 10C here!
 

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Hello Team!

Another tale of woe with the A/C in a G! Funny how many problems crop up only when the temperature starts to rise in the UK! 😂

Blowers only blowing warmish air, no matter what settings I use on the HVAC controls. I have just had it re-gassed (470g) as it was completely empty (0g), which leads me to think someone's already had it opened up for problem 🤔

So, compressor is working and it's just had full re-gas. Scanned it, with no faults found. The cooling fan doesn't kick in with the A/C, but does to cool the engine.

Any ideas gents?!
 

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The compressor is definitely working? Fan should come on and off depending on the pressure in system. As it works harder the return is hotter which increases pressure and calls for the fan to cool condenser.
When it was gassed did they test the pressures?
 

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The compressor is definitely working? Fan should come on and off depending on the pressure in system. As it works harder the return is hotter which increases pressure and calls for the fan to cool condenser.
When it was gassed did they test the pressures?
Yes, working 100%. Unplugged the pressure sensor to test it, and the compressor cut off. The AC pipes don't cool down either, so the gas isn't being circulated.

I will have the check the pressures question!

Thank you
 

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I would say either compressor is U/S or the signal to it isn’t working properly. The compressor is a variable displacement type so it can run at different power,it’s not just a straight 12v power supply like older type compressors.

have you got MES to check live data to see what is being demanded?

just realised my wording is probably misleading clutch is energised with 12v but that doesn’t just run compressor like older style. The internals control the variable displacement,no idea how though
 

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Like I said, measure across the terminals of the bit you've now cut off and you should be able to easily replace it. If it's working without it in situ then it's more likely a NTC than not :)
Just tried this with mine it worked blowing cold air again it is an NTE but i cant see any resistance value on it if anyone knows what it should be ill replace it otherwise im blocking the hole and leaving it outside the housing.
 

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That's it! That's the sensor. Just had the garage send over a photo. After they cleaned it, the sensor is no longer throwing codes. For future reference, does anyone know if there is a part number for this thing or does it only come as part of the whole loom? I'd like to save anyone else with this problem some time. It may just be me if the sensor throws a fault again.

Additionally, for any people who stumble on this in the future, there's a higher-res color photo of the sensor attached. Note that the car is a RHD model so this is in the center of the car down near the cabin air filter. Cleaning it with some electronic components cleaner was all it needed.

Unfortunately, the car has thrown faults for three motors in the climate control system now. Supposedly that necessitates pulling the dash off to check the wiring loom and then replacing any motors as necessary. Not sure if it's the loom or the motors at this point. Should be a cool £300 in labor plus £60 per dead motor apparently... Any chance this could be the climate control computer instead of the motors?
Just for futere reference, the a/c is still working after changing filter and cleaning. Really recommend this before bringing it into the shop!
Just for futere reference, the a/c is still working after changing filter and cleaning. Really recommend this before bringing it into the shop!
Hi,

I have the same problem with my 2013 Giulietta.. but then i tried cleaning the cabin sensor and replaced the filter, the aircon worked perfectly fine for 10 days and then started with the similar problem, so i cleaned the sensor again and put it back, would work for a week again, but it does not seem to solve the problem.
I do not know if the sensor is loose and would work only at a particular wiring angle??

how is your car's aircon doing now, is the issue revolved?
 

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Hi,

I have the same problem with my 2013 Giulietta.. but then i tried cleaning the cabin sensor and replaced the filter, the aircon worked perfectly fine for 10 days and then started with the similar problem, so i cleaned the sensor again and put it back, would work for a week again, but it does not seem to solve the problem.
I do not know if the sensor is loose and would work only at a particular wiring angle??

how is your car doing now, is the issue resolved?
 
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