OK guys - need some help diagnosing failed Aircon on a 2001 Fabia.

The system has generally worked fine for the last 9 years but was recharged in May 2007 (approx two years ago) by a main dealer due to it not getting as cold as it could do.

Over the last couple of weeks or so I've wondered if it has been working properly as it doesn’t seem to have been getting overly cold again and may have only been working occasionally (although the windscreen has misted up after turning it off so I guess it must have been doing something).

However, last night I pressed the button and... Nothng - absolutely no cooling whatsoever.

So I've checked the fuse and had the glovebox out to check all the connections and that the recirc flap etc. is working. I've also had a look under the bonnet and the Aux belt is fine, the compressor appears to be spinning OK and I can see no bits of plastic lying about suggesting something is busted inside it. I've also checked the connection to the compressor so what is next to look at?

I'm guessing gas pressure but given it was supposedly re-gassed in 2007 and seems to have been working (albeit I'm not certain) could it be that?

And what about the EVAP sensor? - is this a more likely culprit if it has just given up completely?

Suggestions on a postcard ASAP please (given this week is forecast to be the hottest so far this year!)

I'd say it's the gas dude, it doesn't last forever, especially after it's been done once and it was 2 years ago you last had yours done. Take it to Quik Fit - it's around £30.

Do you have access to vag-com? If it is the evap it should have a fault code.

Also does the aircon radiator fan come on?

Do you have access to vag-com? If it is the evap it should have a fault code.

Also does the aircon radiator fan come on?

Re Vag Com - no not readily but was considering buying a simple code reader anyway (would this show the AC codes though...?)

As for the rad fan - not that I'm aware of - I ran the car for about 15 miutes on tickover yesterday afternoon with the AC and recirc on to see if it was cooling and did the same again last night and don't recall seeing the fan fire up...

A hand-held reader will only show engine codes, although if you have a failed evap sensor, you should be in the situation where you get cold air when you first turn the car on, but not after everything's warmed up (not 100% foolproof, but accurate IME ) I'd also recommend a refrigerant level check as your first port of call. OTOH, does the 'AC' light actually come on when you press it? It can be hard to tell in this light, but the control unit failed on my wife's a little while back...

Like I say, get the gas checked first, otherwise:

Evap temp sensor

AC control panel

Thanks ap0gee,

I'll check if it works when cold this evening but I have a sneaky suspicion it was when I dropped it off the drive to get the Mazda out this morning...

The lights are definitely coming on so that should be OK.

I noticed that your link suggests the sensors aren't waterprrof which suggests I may have buggered it last week... I had a go at de-smelling my air con last week and sprayed some anti-bacterial spray into the system from the pollen filter opening so that might just have signed the sensors 8 year old death knell!

I'll maybe pick up an EVAP sensor this lunchtime and have a play tonight with your guide and then check the gas tomorrow.

Cheers!

I don't think cleaner would do any damage, considering how much condensation must be inside the system on a humid day. In terms of it working when it's cold, what I really meant was when you first start the car and the engine's cold, but giving it a go when it's cooler in the evening will help, I guess. Good luck getting it sorted - if it is the sensor, then I think it's a job that ranks up there with console bushes and you should get some some sort of Brisky medal!

I don't think cleaner would do any damage, considering how much condensation must be inside the system on a humid day. In terms of it working when it's cold, what I really meant was when you first start the car and the engine's cold, but giving it a go when it's cooler in the evening will help, I guess. Good luck getting it sorted - if it is the sensor, then I think it's a job that ranks up there with console bushes and you should get some some sort of Brisky medal!

Re the cleaner it wasn't one of the "normal" car AC cleaner aerosols - more like Dettox multi surface cleaner that I sprayed in there for a laugh to see if it would work (and it did appear to get rid of the smell - just with a possible side-effect :(.)

Anyhow I realised you meant a cold engine and the car is not being used today so the wifey just had a go and "thinks" it was coolish air coming out...

So 've picked up a sensor and will get one of those R134a recharge cans on the way home from Halfords...

you should get some some sort of Brisky medal!

Already gave myself that for fitting a CD changer in the boot a year or so ago - making a mounting box for it for the boot and running the changer cable from the dash to the boot under the carpets along the centre console was a cracking job (the latter resulted in most of the interior coming out).

OT, but I just poked the cable for my changer behind the O/S sill trim, and put the mounting bolts for it through the carpet on the side of the boot!

The sensor inside the dash is common to failure as is the compressor on Fabias. The rest is quite reliable according to my a/c man. A Vag.com scan is the best line off attack first. Followed by a regas.

OT, but I just poked the cable for my changer behind the O/S sill trim, and put the mounting bolts for it through the carpet on the side of the boot!

Vagcom is the key.

But the most common failures of aircon systems are. No gas due to either a leaky seal, condensor, or compressor. Have a check of the condensor make sure its not been hit by a stone etc, this is very common.

you say the compressor is spinning? but is it, all earlier types have a magnetic clutch, so the outside of the pulley spins, but the inside remains still untill switched on.

The radiator/ condensor fan should spin all the time the aircon is switched on, to maintain a condensor pressure of around 16 BAR. If there is no gas in the system, the fan will not run.

If the pressure sensor is faulty, again the system will not work, no fan etc.

More modern aircon systems have done away with magnetic clutches, and now use a duty cycled swash plate within the compressor, so the compressor can never truely be switched off, these are generally more reliable than the mechanical magnetic systems, and much more effeicient and controllable.

So key things to look at:

1. any signs of damage to condensor.

2. is it a magnetic type compressor.

3. Do either of the fans run at a constant speed.

My bet is on a leak somewhere.

Matt

Just so you know, when i was a techie for VW and Audi i was the Aircon specialist.

More modern aircon systems have done away with magnetic clutches, and now use a duty cycled swash plate within the compressor, so the compressor can never truely be switched off, these are generally more reliable than the mechanical magnetic systems, and much more effeicient and controllable.

Anyone know when this was changed over ?

Rick

Not sure, but i have just checked on a 04 Fabia, and it list the magnetic type.

New duty cycled type seems to be from model 2009.

Mine packed up due to a corroded pipe, the pipe is special and only available from skoda at £170+vat +£40 to re-gas and £80 to fit as the front bumper and radiator have to be removed.

So at over £300 it was a no go, suffering for it now though

Not sure, but i have just checked on a 04 Fabia, and it list the magnetic type.

New duty cycled type seems to be from model 2009.

That's funny, as I have it on fairly good authority that ALL Fabias have a wobble (swash) plate compressor :confused:

If fault codes can be generated, does the driver get any fault system indication of malfunction, other than the obvious absence of chilled air, say a flashing air-con light ?

That would save an awful lot of costly repairs - I understand that the coolant also acts as the compressor lubricant.

http://briskoda.net/fabia-i/air-con-feeble/150272/

Nick

No lights on the dash or AC panel when mine ran dry, however a fault code was stored - really useful, that! :rotz:

That's funny, as I have it on fairly good authority that ALL Fabias have a wobble (swash) plate compressor :confused:

All Fabias from 2000 use the more modern compressor. There is also a fail safe low pressure cut off to protect the compressor lubrication if coolant drops too low.

All Fabias from 2000 use the more modern compressor...

That's pretty much ALL of them, then? I'm not sure I'd claim a clutched centrifugal pump was more modern than a wobble-plate compressor, though? :confused:

Well a result today - I didn't have time to get to Halfords and figured that I could just be chucking £40 down the drain for a can of refridgerant and £20 down the drain for a sensor so took it in to Kwik Fit for them to recharge it (normally I wouldn't go near the place) watched them hook it up the machine, made sure they got the correct model, engine and year in the machine (the guy thought it was a Felicia to start with!) came back half an hour later to see that it was still connected and had nearly finished checking for leaks (if there is a leak the machine just stops and won't refill), gave it another ten minutes and bingo - cold air ensued big style!

So thumbs up for Kwik Fit on this occasion.

Hopefully that is the way it will stay that way and if anyone wants an EVAP sensor for £20 let me know!

Well teh AC has died again... I wasn't too surfe on Friday on the way home whether it was working or not (short journey!) so tried it properly today (Sunday) and it is dead again - nil, nada, nothing!

So having had it checked for leaks and recharged and getting it working for... oohhh all of half an hour... it is dead again.

Evap sensor?

So you had it recharged, it worked again? now its dead again?

Would seem you have a leak.

Did the recharge include a vacuum leak test for at least 45 minutes?