VCDS and Aircon

[2SkodaFamily]

Hi,

Looking to fix the aircon on my wife's Fabia. I replaced the fan resistor last weekend as the fan didn't work on speeds 1 & 2. I knew that wasn't what was stopping it from working but decided to replace it anyway.

The aircon hasn't worked for at least a year.

I've connected up with VCDS and established that the compressor load peaks at 80%, and refrigerant pressure is between 2.2Bar and while sat on the drive with the engine idling, I saw it peak a bit over 6Bar. The compressor shutoff code is 0 when the AC is switched on, and shows a 6 when I turn the AC off.

I'm no expert but it seems to me that there can't be a big leak anywhere (such as a hole made by a stone) because there is still some pressure in there, albeit not much. I am guessing that the pressure should be a lot higher than 2Bar. The fact that the pressure increases roughly threefold tells me that the compressor is running, and it's succeeding in gaining some compression.

VCDS gave the following fault before I started.

65535 - Internal Control Module Memory Error

00-00 - -

01596 - Motor for Outside/Recirculated Air Flap (V154)

41-10 - Blocked or No Voltage - Intermittent

00819 - High Pressure Sensor (G65)

07-10 - Signal too Low - Intermittent

I reset these, ran the system for a while and went for a drive, and was then presented with this:

01596 - Motor for Outside/Recirculated Air Flap (V154)

55-00 - Adaptation Not Successful

It's interesting though, that the 00819 High Pressure sensor fault hasn't come back.

Any further thoughts on this?

thanks

Martin

[2SkodaFamily]

Does the fact that the reset on the flaps failed stop the system from working? Even though the compressor seems to be running?

[2SkodaFamily]

Oh, and did I miss it or do the measuring blocks on the Fabia not include compressor current actual vs specified.

[mitcho_man]

Hello! You may have sorted the AC out by now. But incase you haven't... 2bar with the AC off is far too low. Generally, at around 15*C (bearing in mind the engine bay may be hotter than ambient temp) the refrigerant pressure should be around 5bar with the AC off. This should rise to around 9-10ish bar with the AC on at 2,000 rpm. My guess is a lack of refrigerant in the circuit. Maybe due to a VERY small leak. Or, if the car hasn't been regassed for a few years, then just due to natural loss of the refrigerant. 80g lost per year is permitted on slightly older vehicles. So if your AC circuit was charged at one time with 525g of refrigerant... After a few years, it could have naturally lost as much as 240g. This would make a big difference to the pressure in the circuit and to the cooling performance.