Octy RS Air Con Electronics

[dswhite]

Hi all,

I'm hoping one of you can help me:

I've a 51 plate Octy RS which since the winter has been lacking Air Con. The Climatronic system all seems to be working, but the air coming out of the vents doesn't get cold. I assumed that the system needed a re-gas, so had a local garage to me re-gas it last week. They said that the system wasn't that low, but topped it up anyway. Unfortunately the system still doesn't work. After some detective work at lunch, I worked out that the compressor wasn't engaging. I stuck a multimeter on the two wires going to the compressor and I get a constant 9 volts irrespective of what the climatronic is set to (This doesn't seem right to me - I'd expect 12V or 0V, to engage the clutch). I decided to try running the compressor manually by putting 12 volts from the battery onto the terminals, and you could hear the compressor clutch engage. I then repeated this with the engine running and hey presto! I had cold air coming out of the vents!

Anyway, the question at the end of all this waffle is does anyone have any theorys as to why the compressor is not being engaged? I'm wondering if it could be the relay driving the compressor (I assume there is one), so if anyone knows the location of said relay that would be useful.

Plan B is to get another of my local garages to plug a VAG-COM box into it and see if it can be diagnosed.

Incidentally, I had my local Skoda garage read the fault codes from the ECU last month when a temp sensor went, and there was no other faults logged, so whatever the problem is it's not been detected by the ECU!

Any help or suggestions would be gratefully recieved!

David

[ScoobyChris]

Not sure if it's the same as the Octy, but my Fabia's "Evaporator Temp Sensor" packed up which meant that the car didn't engage the air con. It showed up on VAG-COM as a sporadic fault though! :confused:

Chris

[dswhite]

Thanks for the reply. I think it might be something like that. I've had one temp. sensor on the engine pop a few months ago - these sensors don't seem to be hugely reliable!

I think i'll have to get a cable shoved up it and see what it says.

Dave

[dswhite]

Just in case anyone else gets a similar problem to this, here's the suspected problem:

After some poking around by an air con specialist, it appears a relay that controls the air con (Part no. W1J0 919 506 K @

[mannyo]

Keep us all posted, sure sounds like a weird problem.

[Tech1e]

Do me a quick favour. On the two pin plug on top of the compressor with a test light probe one of the connectors and see if you get 12v. If you do connect up the other wire to earth and with it all plugged in operate the a/c and see what happens. What often happens is the earth that goes from that unit across the top of the starter motor breaks and the compressor looses its earth.

[drlargepants]

I think I have the same issue. I've just had the compressor replaced, and the aircon still isn't working.

Where's the best place to start, vagcom ?

[superfredin]

hi. check secret codes for climatronic...

[drlargepants]

OK, which ones should I look at ? The temp values look OK

[Theresias]

Start checking the shut-off codes i the meas. blocks and the refrigerant pressure. Those are usually a good start and give you a detailed clue what the problem is.

[drlargepants]

Is there a list of all the codes anywhere, the one I have doesn't seem to include what you mention ?

[Kenny R]

Found this on here previously,might be of some help

climatronic diagnostic.txt

[drlargepants]

thanks

[drlargepants]

I get 6 volts at the compressor regardless of if the aircon is on or not. Any ideas ?

[Theresias]

The voltage doesn't matter much because it only tells you what you already know, the compressor doesn't come on. The real question is why doesn't it come on and that's what the shut off codes tell you!

[drlargepants]

OK here are the results of the codes from the climatronic unit

There is no pressue in the refrigerant as (apparently) you need the compressor to engage to draw the refrigerant in so there is hardly any in there now

climatronic%20diagnostic[1].txt

[Theresias]

Maybe you should use a real diagnostic tool or let somebody deal with this who has access to one, we have seen enough cases by now where the button-play-codes were misleading at best... Who tells you that the list you refer to is correct for your model? Nobody because no official repair manual contains them and they are all hear say.

[drlargepants]

i have vagcom,\ but i haven't got a clue what i'm looking at. It detects the inteface, but doesn't seem to retur anything when you do an autoscan

[DizMeisTa]

these prices and all this debate gets me worried about my octy vrs. doesnt blow cold either!!!

[drlargepants]

Get it looked at ASAP, may just be low on gas. Thing is I replaced the compressor on mine having been told that it was FUBAR by the garage, but now it would seem its something electrical. Not best pleased!

[DizMeisTa]

had it regassed b4 i bought it. my m8s dad(fella i bought it off) said he doesnt know what it is. mind you i thinkin far too ahead of myself. garage hasnt even started the repair work from some stupid woman crashing into me. sigh!

[auroan]

Has anyone done what Lummox suggested ?

[drlargepants]

Not yet, I wasn't sure exactly what he ment...

[drlargepants]

got it back from an autosparky and its all sorted now. No idea what they've done, but whartever it was they didn't disconnect the battery...

[Neo_VR]

Just to add to this thread... I recently had my Air-Con regassed at Kwik fit (for a reasonable