A/C compressor clutch

[AAH!]

The dye in my A/C system was/is fluorescent yellow.

Angus

[alg]

Agreed but one of the A/C guys said that dried dye appears like pink staining IIRC when it was been looked at before. IIRC is the issue

[veneto rs2]

Hi there
On my ex S2 3B this kind of problem was caused by the "multifuzzy" sensor that you can see in the picture linked
The ****** controls the A/C on high or dangerous temperature by disconnecting the compressor....... it is also used to send water temperature to the gauge on the dashboard

you have different options:

1 loose the connection and clean very well with a spray contact cleaner
2 disconnect the wire that controls the A/C and forget about it (you have a gauge!)
3 buy a new one (very expensive!)

I reckon that if you have the problem just sometimes it's a good cleaning that's needing

http://img287.imageshack.us/img287/4849/abymultifuzziuswqj5.jpg

Hope this will be helpy

Ciao Stefano

[alg]

Good thought. Would fit with car hot AC no work car cool AC work !!
In today at garage so I will feed back

[A80Avant]

which is the wire on the multifunction switch that controls the A/C??

[A80Avant]

my plug to that sensor was damaged so we used small wire clips to the sensor.could this create any issues???

[veneto rs2]

it's been time since my problem with the S2............
but if i remember well........
it was originally a four pin sender fitted on mine i bought a new one that funny enough had just three pins on it (audi told me it was upgraded....) so anyway if you have a brown wire it's a ground leave it
loose one of the other wires and check the water temp gauge inside the dash if dies then it's not yours
loose another one if the clutch kicks in than that it's the one you need
if you let that one loose the only problem it's for you to turn the A/C off if you have very high temps
My S2 stayed with that cable disconnected for years...........
i'm sure though that somebody in here will have the diagram of that sender.....

Stefano

[A80Avant]

it seems that we have connected everything accordingly cause i am getting readings on the gauge.If the other 2 wires are wrong,could that create an issue concerning the temp difference between the ecu temp sender and the MFTS?
i believe they have nothing to do with that.
Either my wire connections to the MFTS somehow create a different reading due to amp or volt difference or my ecu temp sender is reading something else

[alg]

Well guess what the AC worked without issue at the garage. However the red sensor to the condensor ? high pressure sensor is cracked. Could this be the issue ? If I replace it can I do it without releasing AC gas ? That is does it shut off at the condensor when removed

[alg]

More news. Vagcom one code 'no signal to A/C control unit' It was working when codes pulled so not sure if helpful. IIRC from all my recent research the manual unit only stores codes until ignition next off.

Looked at lots of threads and made an 'educated' guess re MFTS as it shuts off A/C when coolant temperature too high.

Disconnected it today with same issue i.e. AC worked before drive then stopped when ambient and/or ehgine temps were high (not extreme).

Boost seemed better however so I will replace the MFTS (original 4 pin) anyway. Could actually be due to higher temps today down here in Yorkshire as IIRC boost goes up as temp does to maintain performance.

So can anyone tell me what other sensors 'talk' to manual AC apart from MFTS and ambient low temp sensor in heater inlet tract ?

Does the ECU 'talk' to the AC apart from brief cut off under accleration and idle speed stabilisation which do not fit the problem

I plan to replace the MFTS & G62 coolant temp (which if the ecu does talk to the AC may solve it)

I will also replace the high pressure switch on the condensor as it has a split in plastic but I do not think it is related to the fault which appears temp related.

[A80Avant]

i dont think you have any issues with your MFTS as here in Greece i have temps around 35C on the outside temp display,MFTS sends signal to 95C of the coolant temp and A/C still works sending cold air.

[alg]

Solved see http://www.s2forum.com/forum/showthread.php?t=23950