Radiator Fans part 3 - R32OC

dubzter · 25th June 2009, 12:19 PM

Leading on from these 2 posts
http://www.r32oc.com/performance-tec...ator-fans.html
http://www.r32oc.com/performance-tec...-part-2-a.html

Well I replaced my radiator Temp Switch last night and the fans are now working woohoo................................
but only for engine cooling boohoo.

So I need to identify why they are not working for the aircon.

Does anybody fully understand the aircon system on a MKIV?

When the climatronic is set to Auto the fans don't turn at all, the outside temp was 14 degrees last night so it wasn't that.

If the gas in the aircon system is out would the aircon still function as if it were ok? eg fans would turn?

I don't know where to go from here, but the good thing is I won't overheat the engine.

Help please!

DWolfUK · 25th June 2009, 12:46 PM

do you get cold air? can you hear the engine revs drop? could still be that the slow speed fan side is broken. but least this can be fixed with a kit.

if the gas is low (or high) the fans wont come on and the compressor wont engage.

dubzter · 25th June 2009, 12:51 PM

I think the revs do change when I switch between econ and auto. But no cold air.

The fans cut in on slow when the engine recahes the correct temp.

Bypassing the temp switch both fans worked at slow and high speed so the fans are fine

DWolfUK · 25th June 2009, 01:06 PM

ok so the fans are obviously fine in that case.

gotta be pressure in that case i think. if you start the car and open the bonnet. listen and see if you can hear a click from the engine bay when turning ac on and off. set it to the lowest temp and then rev the car and you should hear the ac compressor re-engage a second or two after the revs drop (is disengages when you rev the engine)

dubzter · 25th June 2009, 01:10 PM

its hard to hear as the sup[ercharger drowns out quite a lot of the noise. I'll get her up on the 4 post ramp and see if I can hear it better underneath.

I hope I don't need a new compressor

DWolfUK · 25th June 2009, 01:22 PM

not likely. when mine went it was just the clutch and was easy to sort from underneath without re-gasing etc.

sounds more like pressure to me and so id be tempted to try re-gassing first. i cant for the life of me remember if theres a sensor to tell if the compressor's working or not. i dont think there is so you should get fans even if its just for a few seconds before the pressure sensor recognises the pressure hasnt increased.

blackpug · 25th June 2009, 05:23 PM

I think it needs regassed too. My last Gti had the same symptoms. I regassed myself with a kit from Ebay.
I also found this :

How to Diagnose A/C System On 2000 VW Jetta GLS

dubzter · 25th June 2009, 05:40 PM

Quote:

Originally Posted by blackpug

I think it needs regassed too. My last Gti had the same symptoms. I regassed myself with a kit from Ebay.
I also found this :

How to Diagnose A/C System On 2000 VW Jetta GLS

something like this?
CAR AIR CON SYSTEM REGAS RE GAS REFILL RECHARGE AIRCON on eBay (end time 30-Jun-09 16:44:13 BST)

blackpug · 25th June 2009, 07:19 PM

Yes, but it wasn't as dear as that.

blackpug · 07:27 PM

Think I got mine here via ebay :

DIY Products*::*Autokool

Alexis · 26th June 2009, 04:03 PM

Dubzter, it appears that the air con is linked to the fans. As you are aware of the problems i had with mine that the slow fans & air con weren't working after it was regased as kwik fit, i went to fit the nime resistor module and found that one of the wires from the fan control module (under the battery tray) had snapped. I repaired the wire and now both slow fans & air con are working.

So it's worth having a look at your module connections. If you need any help just let me know.

DWolfUK · 26th June 2009, 05:03 PM

hes tested the low and high speed fans so the control module seems ok. but yeah its defo worth checking

dubzter · 26th June 2009, 06:05 PM

cheers guys, I didn't really check the connections of the control module under the battery, guess I should've as I had the battery out to replace the temp switch. Will check it out tomorrow, off out for a curry and a pint tonigh

Alexis · 26th June 2009, 10:07 PM

Is the air con still blowing cold air? If not take it to kwik fit get it emptied & regased and if no different then it's fully regased free of charge for when you find the fault!

That's excatly what I did, they emptied it did a leak test and regased it free of charge so i came home found that broken wire fixed it....bonus £45 in my pocket!!

DWolfUK · 27th June 2009, 12:15 AM

hope you enjoyed the pint lol

id bet on it simply needing re-gassing but it cant harm to cover all the bases. specially if you can yourself and it wont cost garage fees.

most places will re-gass and re-gass again free if that doesnt cure it once you find the fault.

dubzter · 27th June 2009, 12:37 AM

Guys, just home, bit worse for ware. Think I'll go regas first, if that doesn't work then l need to think again