Aircon not working - diagnosis

[bennettp]

Hi,

Seat Ibiza 1.2 2017 (not newest shape).

Aircon not working. Took it for a regas to Kwik Fit they said the compressor is not kicking in. I assume they have regased it, when pressing the nipple under the pressure switch there is some pressure (but obviously I don't know if that is enough). They said new compressor £650. I'm 18 on a part time job so would like to double make sure it is a new compressor as I can't afford that .

1. Got a new pressure sensor (albeit of eBay) - 3 pin.
2. Fitted that and when the aircon is switched on the radiator fan goes straight to high speed.
3. I tried it off the pipe ie. just plugging the wire connector to the pressure sensor without it being installed - radiator fan straight to high speed.
4. Tried that with the old sensor - nothing happens - no radiator fan on high speed.
5. Measured the connector pins and found one to be 15v so I think that is fine as the other is the signal and other ground?
6. So definitely a different behaviour between old and new pressure switch but still no cold air.
7. Is there a way of definitively saying its the compressor and not something else?
8. Could there actually not be enough gas in and so the new pressure sensor works but the fan goes on high because of that?
9. Can I just leave the senor plug off for now or will that stop the radiator fan working and the car will overheat?

I'd really appreciate any help.

Thanks,

Bennett