Aircon not working diagnosis

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
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anditsoundslikebells
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Aircon not working diagnosis

Post by anditsoundslikebells » Fri Jun 18, 2021 2:13 pm

thought I had it all fixed, of course not.
My aircon has decided not to work, of course, while it's nearly 30 degrees.
Does anyone know if I'll be able to diagnose with OBDeleven? I don't have VCDS.
Aside from a diagnosis is there another way I can check anything?

I've probably not used the aircon since the engine&gearbox was out in Poland. I was told they put the gas back in but maybe that is a simple solution.
Is there a way to check the aircon gas levels?
RS6 C5 Avant 2002 Daytona Grey
TTH 620 - Wagner IC - OC.T 200cell&downpipes - DW400 pump - 034 TCU chip - FIS - B16 PSS9 - 034 control arms - H&R ARB - OZ Superturismo

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Shoppinit
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Re: Aircon not working diagnosis

Post by Shoppinit » Fri Jun 18, 2021 2:49 pm

Yes. Get a gauge kit. Like this:

https://www.ebay.co.uk/itm/174732373632 ... SwKeBfJAgO

To check for pressures.

The high and low side pressure readings will tell you a lot about how the system is working (or not).

Most common failure on the RS6 AC is the high pressure switch. If you're lucky it's just that.

If the engine has been out, I'm betting that the AC hasn't been put back together properly. Maybe the compressor is dead now. They don't like contamination.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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anditsoundslikebells
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Re: Aircon not working diagnosis

Post by anditsoundslikebells » Tue Jun 22, 2021 8:19 pm

I took the 6 to the normal garage (MP Carworks) as I don't have a VCDS.
The error was relating to a G263 sensor. We looked up where that is, didn't really appear to relate to our cars but it was only under the glove box. Pulled that out and the sensor hole was blocked off.
It transpires that the climate systems was set up for a diesel car.... we amended the codes to reflect the 6 and 'click' I had cold aircon.
I think this happened before I bought the car and I'd not used the aircon before.
Probably the only 20euro trip to the garage I will ever have!
RS6 C5 Avant 2002 Daytona Grey
TTH 620 - Wagner IC - OC.T 200cell&downpipes - DW400 pump - 034 TCU chip - FIS - B16 PSS9 - 034 control arms - H&R ARB - OZ Superturismo

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Shoppinit
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Re: Aircon not working diagnosis

Post by Shoppinit » Tue Jun 22, 2021 8:33 pm

That’s a weird one.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

Mɐʇʇ
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Re: Aircon not working diagnosis

Post by Mɐʇʇ » Tue Jun 22, 2021 9:41 pm

What would the symptom of the AC system being over charged? I had mine charged up a while back and I tends to cause the belt to slip sometimes now.
Have cleaned the pulleys and replaced the belt. Still does it
"not a professional engineer, mechanic and mechanist"

Foxmeister
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Re: Aircon not working diagnosis

Post by Foxmeister » Wed Jun 23, 2021 9:04 am

anditsoundslikebells wrote:
Fri Jun 18, 2021 2:13 pm

I've probably not used the aircon since the engine&gearbox was out in Poland.
Maybe something to do with these lads when putting the car back together, changed some settings or software possibly and used generic A6 settings?

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Shoppinit
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Re: Aircon not working diagnosis

Post by Shoppinit » Wed Jun 23, 2021 9:07 am

Mɐʇʇ wrote:
Tue Jun 22, 2021 9:41 pm
What would the symptom of the AC system being over charged? I had mine charged up a while back and I tends to cause the belt to slip sometimes now.
Have cleaned the pulleys and replaced the belt. Still does it
Not good if it's overcharged. You could kill your compressor. Get some AC gauges. They are cheap and will tell you instantly what your low and high pressures are. I'd expect your high pressure switch to protect the system somewhat but if it's kicking in you should get codes.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

Mɐʇʇ
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Re: Aircon not working diagnosis

Post by Mɐʇʇ » Wed Jun 23, 2021 9:13 am

Is this the type of thing I need? https://www.ebay.co.uk/itm/284299472683
Time to learn about air conditioning myself after being let down by paying for someone to do it....... ;)
"not a professional engineer, mechanic and mechanist"

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Shoppinit
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Re: Aircon not working diagnosis

Post by Shoppinit » Wed Jun 23, 2021 9:48 am

Yeah, but get one with the quick release connectors. The one I bought was this one:

https://www.ebay.co.uk/itm/254390382751

Confirmed there was no gas in the Saab.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

Mɐʇʇ
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Re: Aircon not working diagnosis

Post by Mɐʇʇ » Wed Jun 23, 2021 9:57 am

Ta. Ordered.
"not a professional engineer, mechanic and mechanist"

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Shoppinit
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Re: Aircon not working diagnosis

Post by Shoppinit » Wed Jun 23, 2021 9:57 am

Problem is if you want to do open heart surgery on the AC you need specialist gear to recover the gas, decent vacuum pump, etc. It's a pain unless you're doing it every day. Top AC tip: if you are ever getting any work done on it, make sure they put a UV tracer dye in. I found a leak on the dryer on the mitsubishi that way and got the dealer to replace under warranty after they couldn't find a leak.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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Shoppinit
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Re: Aircon not working diagnosis

Post by Shoppinit » Wed Jun 23, 2021 9:59 am

I have just received my OE spec compressor for the Volvo from Rockauto. I traced the AC problem to a borked clutch. It was cheaper to buy a whole new compressor from the USA than just the clutch from Volvo. :shock: I really, really don't want to change the compressor so I am hoping I can do a clutch transplant with the AC system intact. If not then I'm just gonna get Volvo to do it at a cost of probably more than a grand and I'll have bought the compressor for nothing. I hate AC problems.

/BTW, if you thought the RS6 was a nightmare to work on, you should try the XC90 V8. Same stupid size-13 engine shoe-horned into a size-9 engine bay, but this time it's transversal. :shock: Took me 2 days to change the alternator and I thought I was going to go mad.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

Mɐʇʇ
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Re: Aircon not working diagnosis

Post by Mɐʇʇ » Wed Jun 23, 2021 10:11 am

Oh.
Shoppinit wrote:
Wed Jun 23, 2021 9:57 am
Problem is if you want to do open heart surgery on the AC you need specialist gear to recover the gas, decent vacuum pump, etc.
"not a professional engineer, mechanic and mechanist"

Mɐʇʇ
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Re: Aircon not working diagnosis

Post by Mɐʇʇ » Wed Jun 23, 2021 10:13 am

Subframe drop?
Shoppinit wrote:
Wed Jun 23, 2021 9:59 am
/BTW, if you thought the RS6 was a nightmare to work on, you should try the XC90 V8. Same stupid size-13 engine shoe-horned into a size-9 engine bay, but this time it's transversal. :shock: Took me 2 days to change the alternator and I thought I was going to go mad.
"not a professional engineer, mechanic and mechanist"

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Shoppinit
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Re: Aircon not working diagnosis

Post by Shoppinit » Wed Jun 23, 2021 10:17 am

Probably would have made sense, but I read it could be done without. And it can... just.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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