8l s3 air con fan not working help

8YA335TDI1STED

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Hi folks having read the aircon faq post i decided to go out and check if my air con fan works , outside temp was an indicated +6.5c set the temp to low I then switched the econ button so that the light went off none of my rad fans were spinning where should i start looking for the prob ? anyone got a link or diagram of the fuses so i know which one to check ?
 
You will probably have more luck with that sort of question in the 8L forum, but doesn't the fuse box show you which fuse anyway?

Does the radiator fan work once the engine is hot?
 
You will probably have more luck with that sort of question in the 8L forum, but doesn't the fuse box show you which fuse anyway?

Does the radiator fan work once the engine is hot?
havent looked in at the fuses yet Staz just had the car a few weeks , however after my recent stat and coolant fluid change i discovered my rad fan cuts in too late close too 110 deg so looking at changing the temp sensor and fan switch , does the temp sensor have any connection with the ac system ? and how can i test the ac system for fault codes without vagcom ?
 
The temp sensor shouldn't have anything to do with the air con so I'd say it's unlikely that the two faults are connected. I may be wrong though, of course lol

I don't know about checking for fault codes without VCDS but you'd be better of with it as you'd get a better indication of the fault cause. Do you know about the VCDS users map (in my sig)?
 
The temp sensor shouldn't have anything to do with the air con so I'd say it's unlikely that the two faults are connected. I may be wrong though, of course lol

I don't know about checking for fault codes without VCDS but you'd be better of with it as you'd get a better indication of the fault cause. Do you know about the VCDS users map (in my sig)?
thats very helpfull Staz unfortunately no one in my area how much are these kits to buy is there a mini version for home owners ? also read that it depends what cable you have whether you can do a proper diagnosis , my m8 who has been doing my service has some sort of unit which plugs in and has different keys to attach for different vehicles is this a vagcom ?
 
VCDS is the new name for Vag-Com which is produced by Ross-Tech. It's only for VAG cars AFAIK. There are other systems that cater for lots of types of cars but VCDS is very good and comprehensive and is definitely more than enough for a home user. It's not that cheap though I'm afraid but if you plan to stay within VAG for any length of time it'd be a worthwhile investment.
 
this will be my 8th Audi /vw car last car was a 520 bm inbetween ive had 3 bmw cpl of fords and cpl of vauxhalls in the early days i may add ,oh and a cpl of volvos unfortunately the amount of probs ive had too put right with the S3 reminds me why i switched to BMW in the first place , having set that aside ive come back looking for reliable performance , ive spent close to 1k on servicing the s3 in the last 4 weeks , new timing belt, 4 new boots, oil andl filter, spark plugs , fuel and air filter, and various other tweaks , ive bought a copy of elsawin which seems to work ok but cant find a good copy of etka , as yet . just hoping i can service the car myself without the huge costs of diagnostic tools which i would happily buy at a fair price .
 
Well it's just down to you to decide mate, but if you have a mate in the trade then it's probably going to be easier to use his kit I would say.
 
Well it's just down to you to decide mate, but if you have a mate in the trade then it's probably going to be easier to use his kit I would say.
no worries will try a post in the 8l forum see how i get on thanks again Staz
 
the fan control module controls the following........

electric water pump
air con compressor
both fans

if you have problems wiht the above change / look at the 3 fuses on top of the battery first i think the one of the left is what you want to look at, the other 2 control the ABS

failing that, change the fan control unit part number 1j0 919 506k, euro car parts sell them and let you send it back if it does not fix the problem.....
 
the fan control module controls the following........

electric water pump
air con compressor
both fans

if you have problems wiht the above change / look at the 3 fuses on top of the battery first i think the one of the left is what you want to look at, the other 2 control the ABS

failing that, change the fan control unit part number 1j0 919 506k, euro car parts sell them and let you send it back if it does not fix the problem.....
Hi m8 thanks for that info , ive also been having problems with the rad fan not cutting in on time and temp kreeping up to 110 deg on the dash b4 it switches on and thats after ive just changed the stat and coolant , I was suspecting the fan cut in switch and or temp sensor on that ground but you say the fan control module controls both fans so this could well be the place to look first , could you tell me where is it located and also where is the electric water pump ? do you mean the ones that supply washer fluid ?? cheers ??
 
Hi m8 thanks for that info , ive also been having problems with the rad fan not cutting in on time and temp kreeping up to 110 deg on the dash b4 it switches on and thats after ive just changed the stat and coolant , I was suspecting the fan cut in switch and or temp sensor on that ground but you say the fan control module controls both fans so this could well be the place to look first , could you tell me where is it located and also where is the electric water pump ? do you mean the ones that supply washer fluid ?? cheers ??

the s3's have an electric water pump, it helps cool the turbo down when the engine is turned off, it runs for about 3 minutes after the car is turned off, it is located on the top left of the radiator (facing the car), if you dont hear this when you either turn the igniton on (engine does not need to be started) or when you get out after a run, chances are you have a problem with the mentioned part.

i had the exact same problem as you, it wasnt my controller unit, but the fuse i mentioned! i made the mistake by changing the part first (AA guy told me the fuses were ok, they were not!) i did just have a look for the old module and i can not find it ugh!

i bet you it's the fuse, i bet it has plastic residue on the contact from where it has got hot!

oh and the part i am refering to is under the battery, it's easy to get to if you remove the battery and battery holder.
 

thats great info m8 ill deffo give that a try as soon as the weather lets up, when you changed the fuse did your rad fan then kick in at a lower temp ?
ive allready priced the fan cut in switch and temp sensor circa £60 for both so heres hoping its the fuse , I do hear my electric water pump always wondered what it was that made the noise so its working ok
 
i had multiple problems, changing the fuse got my air con compressor working along with the fan that should run when its on and if the aircon was off, the fan would come on to stop the car from overheating!

sadly, my fan does not come on now if the air con is off (which happes a lot on this weather because it does not turn on when it's below a certain temp outside), so i have bought a new temp sensor and radiator fan switch for £20, don't pay £60, look on ebay!

check the fuses as soon as you can, you'll be suprised!!

If the water pump works, then i fear you could have a problem with the fan and not the fan module / fuse.
 
will investigate on next dry day strangely enough i listened for the water pump tonight after a short journey but couldnt hear it , but ive deffo heard it before cos i had a good look around to see what was making the noise and its a cylinder attched to the top left of the rad looking into the engine bay from front am i right in thinking this pump should be running all the time infact im just off out side to check n see if its working / ok just checked and nope no water pump running noise only thing i heard was a high pitched whistle sound coming from the heater blower so switched that off , still no water pump noise started the engine but it was only at about 70deg still no noise so im gonna have a look at the fuse etc next dry day
 
ok here is the update it stayed dry here today so went to investigate , I pulled the fuse on top of battery the one on the right hand side 25 amp , the spades were absolutely manked up with dirt so cleaned them with some wet n dry , did the same for fuse no16 in the dash its a 10 amp job , turned the ignition to position 1 and sure enough the electric water pump came on , took the car a blast to reach full op temp and tried the aircon on low auto and recirc , NO FAN ON :banghead:, switched off engine to hear if the water pump was running , NO WATER PUMP :banghead: , It deffo seems to be an intermittent fault with the pump as im sure this should always run once the car is at full temp, although the fuse at battery was dirty i cleaned it up well and tested for continuity and no sign of the fuse melting, i also pulled the other two green fuses and they seemed fine.

I had a look at the diagnostic procedure on elsawin for heating ac and found this procedure for testing the compressor and ac high pressure switch seems quite easy jumper connector 1 and 2 to test compressor function

page 1

http://i176.photobucket.com/albums/w174/cyrusgsxr/compressorhighpressureswitch1.jpg

page2

http://i176.photobucket.com/albums/w174/cyrusgsxr/compressorhighpressureswitch2.jpg

not 100% sure but i think this only pertains to facelift and later models so will have to investigate further, still dosent help my prob though so gonna order up the fan module
 
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Update time

bought new fuses for top of battery 2x 30 amp 1x 25 amp so changed all these
bought a tin of industrial grade non residue electrical contact cleaner and sprayed all connectors concerned
re- bled coolant system just incase any air trapped
removed and dismantled the fan control unit and sprayed all connectors with the cleaner icluding the circuit board and both relays
noticed that someone had been in there before me at some point but all looked well no burning on contacts no dry joints etc
cleaned up the temp sensor ( and noticed it was the original black one )

put it all back together turned on ignition ( no electric water pump) Hmmmm
bled the coolant and waited for the fan to kick in, it came on at an indicated 105 deg C and both fans were spinning very quickly , and stayed on a little while after the display was back at 90 deg C ( this happened very quickly ) this was found in elsawin courtesy of Rossbrownlee

Picked this off Elsa if it helps:

14 -
Radiator fan thermal switch -F18-
q
Switching temperatures: Stage 1 on: 92 ... 97 °C/ off: 84 ... 91 °C
q
Switching temperatures: Stage 2 on: 99 ... 105 °C/ off: 91 ... 98 °C

so seems that my stage 1 isnt working but the car isnt overheating , can anyone sujest a fix or is it a simple case of change the fan cut in switch ?

as for the air con fan aka my original post, after doing all these jobs and re reading the links i posted above , I went and took a gamble and had the air con recharged , sure enough the air con pressure switch was doing its job as the pressure was too low in the refridgerant circuit therefore not allowing the circuit to open , so recharged it and now with temp set at low auto light on econ light off both fans are running on fast speed and the cabin is ice cold lol.

next problem to be solved why dosent the rad fun cut in at speed one only speed two ( poss therno fan cut in switch defective ? )and can anyone tell me exactly when should the electric water pump be on and how to test it and is there a sender switch for it seperate to the fan thermo switch

thanks to any and all who can help cheers Don