Air con ideas please

[Maria]

Air con has never worked in the 4 years I've had the car, but now I need it fixed.
Had a man come out who checked it for gas and said the level is fine, so it does not need re-gassing.
The control panel unit has been changed (for unrelated reasons) and it didn't work before and doesn't work after.

So ... what next?
A fuse?
Compressor?
Any ideas where to look and how welcome.
Also any ball park ideas on what I might expect to pay, also welcome.
Presumably once any part is changed it will then need re-gassing?

 

[Doey1978]

Hi, when mine was like this I replaced the aircon pressure switch and that solved it.

 

[Rich76]

Hi,
What happens when you turn on the aircon? If the compressor is working the revs should drop several hundred rpm at tick over. If you can get a clear view of the pulley on the end of the compressor, you can see if the clutch on that has engaged and is turning the shaft or not. it's hmm not really legal to take stuff off and release the gas into the air, it would certainly need regassing afterwards!

 

[Maria]

No they don't even twitch. But is it the compressor for sure or could it be a fuse or something? Can I be sure it's the compressor? And what kind of money are we talking about for someone to do it? I wouldn't dream of releasing the gas Will see if I can see the compressor in the morning, thanks.

 

[Maria]

Hi, when mine was like this I replaced the aircon pressure switch and that solved it.

Where's that, I have never even looked at air con before

 

[Doey1978]

Where's that, I have never even looked at air con before

It's at the back of the engine, but make sure there's no gas in there 1st as someone has alre

Where's that, I have never even looked at air con before

It's at the back of the engine bay. But make sure its empty of gas 1st.

 

[Doey1978]

It's at the back of the engine, but make sure there's no gas in there 1st as someone has alre


It's at the back of the engine bay. But make sure its empty of gas 1st.

 

[Maria]

Ah ok I'll leave that one to the experts then, as mine is full up. Thanks

 

[BigJase88]

A garage should be able to check if the compressor has power and if it engages

 

[300bhpdaily]

I’m surprised the ac tech didn’t take a quick look while he was there. If it’s full of gas the only thing it could be is the compressor has failed or has no power to it. The hi low pressure switch. Like I say providing the gas is full.

 

[Maria]

I’m surprised the ac tech didn’t take a quick look while he was there. If it’s full of gas the only thing it could be is the compressor has failed or has no power to it. The hi low pressure switch. Like I say providing the gas is full.

He wasn't a car ac tech, he is a buildings ac guy who is happy to test for a fiver and regas for 20 but isn't a car mechanic. Had him look so that if it was just a regas it would be done and if not then I wouldn't pay full price for a regas that wasn't needed or was wasted because there was some other problem. I don't know anything about air con so it was invaluable for not getting conned elsewhere. Because for example Halfords regas without checking the system at all and I wasn't prepared to waste a complete refill without some checks first.

 

[RUM4MO]

I'm very curious as to how your buildings AC guy assessed this system without it running or him removing and weighing and reloading the correct weight of R134A back in. I'd say that all he did was to check its standing pressure, and that will always be the same regardless of how much gas is in there as long as it is enough to keep the pressure at the correct pressure for the ambient temperature. From my limited experience of car AC systems and building Fridge people, they will not touch car systems with a barge pole, which is fair enough, most if not all of them will be running company leased cars that have service support built in, and if the AC is not working, they will get it booked in to get fixed, a bit like horses for courses.

So, where does that leave you, well it sounds like there is some R134A in that system still, so I'd think that the compressor should be able to get enabled when demanded - and that the set of conditions that must be satisfied to allow the compressor to start to run are not being met. If it is short of gas, the compressor would run initially for a short period before shutting down, if the gas was short but only slightly short, the system would also run but not cool down far enough.

I think that this car needs investigating with a proper VW Group full compliant scan tool to try to work out what is wrong, and that might start by checking that the controller is okay, followed by is the compressor control lines being complete. Also is that car old enough to have a clutch controlled compressor drive or is it a variable displacement always driven version of compressor. The pressure sensor is always a possible failed component but I'd only replace that with a genuine VW Group one and they cost quite a bit so no point in just swopping parts to try to get this system working again, using diagnostics should be the way forward followed by good old "getting stuck in " and physically checking wiring ect.

Edit:- I'm in the opposite position to you, I just need a dummy place like Halfords/ATS etc to reload the system in my wife's 2015 Polo so that I can try to find running leaks or just live with it losing gas very very slowly and get the AC back running as currently it is too low on gas charge and I don't feel like wasting my small stock of R134A only for it to escape.

 

[mty12345]

I agree with what RUM4MO says above, it's a very complicated system and VCDS can scan the A/C for fault codes. That would be the way forward IMO.

 

[oggydoodaa]

I agree with what RUM4MO says above, it's a very complicated system and VCDS can scan the A/C for fault codes. That would be the way forward IMO.

How does VCDS scan the A/C? I have one and only just started getting into this sort of thing, what do I do to test it as I've had my LC for about 8 months and the A/C has never worked.

 

[BigJase88]

You actually need the correct pressure in the system. Too much pressure and the system goes into safe mode and will also not operate.

 

[Maria]

I don't know the technical stuff. He had a gauge and connected to some pipe at the front of the engine bay and the dial went up to where he said was roughly right for a car system, and a probe in the air vent.
What he's told me is enough for me to know there is a problem beyond re-gassing and that there doesn't appear to be a leak. I realise he's right about there being more because the revs don't drop.
So back to my original question, what kind of ball-park money should I expect to pay for a proper diagnosis and if the compressor needs replacing, for that?
The car is sound but not in any special condition and the cam belt was replaced 4 years ago - put it this way I don't want to do another cam belt so anything in that kind of price range won't be happening if it's not essential.
It doesn't run at all, never has in the 4 years I've had the car, not with the old control panel and not with the new one either. That said if I switch it on the air seems very slightly cooler.
I have already emailed a car ac guy, just waiting for a reply.

 

[300bhpdaily]

Cost depends on how long it takes to find the problem. If it is the compressor expect the part to be £300 or more brand new plus the regas cost and then the labour time of the person who does the work. There isn’t a generic price for this kinda repair as it’s not the same as a fixed price service.
if I had to guess the ball park figure I’d say
£300 for compressor
£120 for removal and refitting part
£70 for full service and refill of ac system

It could be much more or much less it’s better to ask the person your taking it too for a quote as all of the above prices are guesses to answer your question on wanting a ball park figure.

 

[BigJase88]

Go to a main dealer and pay for a regas they will top up the gas to the correct pressure and then will notify you of any other faults, regas is around £80-100

sometimes they have offers on, i think i paid £60 and they told me the compressor was dead.

£60 for diagnosis anyways so may aswell get the gas changed and sitting at the right pressure.

 

[Homer Simpson]

Get it scanned with VCDS, at least you won't be throwing parts at it although it sounds like it could well be the pressure sensor switch. If it does need regassing, ATS currently have an offer via Groupon

Air-Conditioning Recharge with Optional Antibacterial Treatment at ATS Euromaster, Nationwide (Up to 39% Off)

Cars can have their air conditioning systems recharged and an optional antibacterial treatment provided at locations nationwide

www.groupon.co.uk

 

[Maria]

Thanks guys much appreciated