[Les 57]

I have a 2018 1.9TDi Quattro (B9) with 3 zone deluxe air con. With the engine turned on the aircon automatically goes to "air con off". The rocker switch that allows you to select on / off or eco becomes obsolete. I have pressed the right hand rotary control to make sure it is switched on but still get the "air con off" on the display. With the engine off but ignition on it appears to be indicating as normal but not actually working. The rocker switch and all 3 options are available as is the AUTO function on the right hand rotary control
The fuses located at the end of the dash are ok but I've not got round to checking the others yet.

The system has never been topped up so am wondering if there is some kind of safety cut out if the levels drop.

Any thoughts gratefully accepted.

 

[Dave Kwatro]

It seems to very common for newer cars to have low air con gas! Newer cars and all cars made 2018 onwards use 1234YF gas and in my opinion seems to loose the gas more easily! Seen quite a few newer cars with AC problems and they are mostly because the gas has escaped.

The old gas was R134a

 

[Les 57]

I've still to check the fuses for the compressor etc when I get home but have read a few features on line that the major issue is it's a gas loss fault. I hope it is as its the least expensive option.

 

[Dave Kwatro]

I've still to check the fuses for the compressor etc when I get home but have read a few features on line that the major issue is it's a gas loss fault. I hope it is as its the least expensive option.

But as anything that supposed to reduce harmful emissions/climate change etc it is expensive and that's why the new gas is a lot more expensive, but as you say, not as expensive as a new compressor.

 

[Dave Kwatro]

Let me know the outcome as I was helping another member on here with the same problem on a 2018 A5 too!

 

[Les 57]

I didn't get round to checking the fuses last night so will do them today and let you know if anything's popped. I note there is no warning symbol for loss of A.C on the dash, only the air con off on the ventilation control panel.

 

[Dave Kwatro]

Yep only way to check is by having it 'weighed' by and AC machine to check for loss. It can also be done via VAG com/VCDS by the pressure in the system, but this isn't quite as accurate as weighing it.

My money is on gas loss - if you are getting the light on then goes off when starting engine says the system is active so no fuses blown - I would have thought.

 

[SimonRoma]

Dave is a wise fellow indeed. The new regulations now require that we use this new gas that costs FAR more than the old one and guess what??? Yes, it leaks away much faster!!! OR perhaps the car manufacturers fit just enough gas to make it work and then over to you poor customer!!

When the guy hooks up the machine then it firstly removes the old gas, then checks that your system will hold a vacuum (so has no leaks) and then fills up with the new expensive gas. They will also fit a new cabin filter. Here I pay about 150 Euro for this service with the new gas, used to cost 70 to 80 with the old one. Progress???

 

[SimonRoma]

PS Mate you did not mention how many miles you have covered. AND the experts suggest that the best system is to keep the aircon always switched on so that the system can never dry out.

 

[Les 57]

Phew. Done a bit of phoning around over the weekend with varying outcomes. One suggested I go for a compressor change "as they do break quite frequently on these cars". Most suggest as you guys have, that it needs a recharge. The car is 4 years old and has done just under 40000 miles. I'll be honest and say I wasn't aware of the "new gas" and its limitations. I had it serviced by AUDI only in November but they say checking the A/C is not part of the inspection. Cost of a recharge is around £100 to £150 at an independent garage, hate to think what AUDI would charge.
Thanks for all your inputs. if it's anything more than a recharge I'll let you know.

 

[Dave Kwatro]

Thanks for the update!

News to me about the compressors breaking regularly!! Not sure if it's the B9s, but not heard of any issues with the B8s!

They need to do a dye test first before changing parts, not just go for a compressor change! The dye will show the leak, or should do!

 

[Les 57]

Final update.
I had the system checked and refilled at a local garage. Two days later same problem. Took it back in and after six hours of searching they found a pin prick size hole in the condenser. That was allowing the gas to escape over a period of time. To replace it the whole front end, grille bumper plus one head light has to come off. Will get it done soonest as I'm not in the habit of leaving snags outstanding.

 

[SimonRoma]

Blimey well done phew! Good that you don't need a new compressor!