After spending almost £2,000 getting my engine changed and finally sorted out the cooling fans refuse to stop when the car is switched off.

They run at full speed even with the engine totally cold.

The only way to stop them is to disconnect the battery. There is no 50amp fuse in Fuse 54 under the engine bay fuse cover!

I've been told that I need to replace the whole fan units but surely the fans are ok since they are working - must be whatever controls them to come on?

HELP!!

Theres a thread on here somewhere where someone else had this problem and it turned out to be corroded connections to the fans and the loom.Can,t seem to find it though sorry.

Theres a thread on here somewhere where someone else had this problem and it turned out to be corroded connections to the fans and the loom.Can,t seem to find it though sorry.

mine started over night on their own and it turned out to be a corroded relay which needed the fuse box changing.

Yes there is a thread somewhere

Problem resolved after many hours of searching the site last night.

I blasted warm air around the fuse box under the bonnet and cracked it open and did the same thing. All back together again and it's now resolved. The fans no longer come on when the car is switched off.

Had been told that I would need to replace the fans by a mechanic - would have been an expensive mistake.

There you go, another saving through Briskoda. Time to spend £12

Spoke too soon - the problem is back again.

Looks like it will need new fans.... just add that to the list.... car has had a new engine, brand new turbo and replacement gearbox

Hi, Look at the fan control unit on the base of the cooling fans. Unplug the connectors and they will be green. If you've caught it early enough, you will be able to spray electrical contact cleaner on the pins. If not, you'll probably need the control unit. Fans should be ok though.

HTH

Spoke too soon - the problem is back again.

Looks like it will need new fans.... just add that to the list.... car has had a new engine, brand new turbo and replacement gearbox

Took the connector off earlier but I didn't see any green pins? They looked more like coppery-yellow colour.

Anyway - I sprayed WD40 into the connector and put it back together again and they seem to have stopped again. I'm not holding my breath though.

Finding second hand fans is even harder than finding the engine or gearbox!!

Back on again.... this car is doing my head in.

Is the controller built into the fans or is it replaceable seperately?

Back on again.... this car is doing my head in.

Is the controller built into the fans or is it replaceable seperately?

I had exactly the same problem but with Octavia Mark 1 (2003). Not sure if the fix will be the same but it turned out to be a dud relay switch (located under the bonnet and not in the car). Changed the relay and was then perfectly ok.

The Mk2 doesn't have that relay unfortunately... apparently the controller is built into the fans?

Bought a set of fans off ebay from a Golf so hopefully that'll cure it.

This car is starting to really, really drive me insane. I bought a second hand set of good fans from a VW Golf - fitted this afternoon and all seemed fine. No fans on.

Left it from 1pm today until I came back at just after 5pm - started the car no problem. Turned off and still no problem. I then went into the house and heard the dreaded noise. They are so loud it sounds like a plane is trying to take off through the house. Obviously the controller isn't part of the fans then? So what turns them on or off? Where are they connected to??

I haven't been able to use the car all week - in fact since last February I have only been able to do 3000 miles due to the turbo failure, gearbox issue and new engine required.

Edited 26 February, 201016 yr by rushhour

Turns out the bunch of wires that run along the front of the gearbox had been touching the bottom of the fans and they'd rubbed through the plastic tubing and then rubbed through a number of wires as well. I spent a good while this morning taping them all up and making sure they're well out of the way and it all seems to be fine now. Fans have not been on all day - the first I've actually been able to drive it all week but I still brought a set of jump leads and a spare battery just in case.

Turns out that the above wasn't the cause of the issue because they now still come on every time you turn off the engine.

Getting very fraustrated with the car now since the power steering now also no longer works and no one seems to be able to reset it either. It's like it really does have a mind of it's own.

Hi, I have a similar problem, my skoda 1.9 on a "04" plate, 130 000 miles, the fans stay on as soon as I turn the ignition on. They will not go off until I stop the car and turn the key off. The fan keeps running all the time I am driving - any clues?

i have the same problem my fans keep coming on then off draining my battery is a 2007 octavia lauren and klement 2.0tdi its only done 66k also my heaters dont work anymore and my airbag light is on any ideas

I had a bump in my mk2 octavia last night.

Low speed front end into a micra, cooling fans are on. Had it up to the garage today & they say it's down to the ambiance sensor that's missing, lost it in the accident. Waiting on the part coming tomoz.

G

Similar problem with the fans stopping and starting - draining the battery. Local garage (VW/Audi/Skoda specialist) has traced the fault back to the control unit which, as noted above, is a part of the fan assembly...whole thing is to be replaced leaving me very little change from £500

Update on my previous post - garage just called to say that my problem was actually damp in the fuse box rather than the fan controller. Car now working perfectly and one massive bill avoided.

Big thumbs up to Challenge Motor Company of Cheltenham

my problem has sorted itself out! changed the fuse for th heater and that sorted it even though it didnt look blown!! p.s i dried the fusebox out aswell

my problem has sorted itself out! changed the fuse for th heater and that sorted it even though it didnt look blown!! p.s i dried the fusebox out aswell

Which fuse exactly did you change to sort out your fans ???

This thread saved me a lot of money, thanks.

I'll explain what happened to me, so others can learn from my experience (and stupidity).

Couple of weeks ago a fuse blew, I changed it, all fine, for about a week. Then one morning the battery was completely dead.

Turned out I'd forgotten to put the lid on the (under bonnet) fusebox. It was full with water (told you I was stupid). So I mopped up all the visible water, jump started the car, and it was fine again.

But every time I parked, the radiator fans came on full blast and flattened the battery. Also a few warning lights (power steering, EPS) came on for a few minutes each time I jump started it. Same thing happened every day for a week.

I figured out that I could stop it doing this by either disconnecting a battery terminal, or removing fuse F6 every time I parked, and faced up to the possibility of an expensive repair job (new ECU?).

Then I saw this thread, hairdryered the inside of the fuse box for 15 minutes, and it's been totally fine.

Odd that moisture in the fusebox had only this one very specific effect, but not entirely surprising.

Makes me sound quite stupid this, as the solution is totally obvious, but there you go.

Had problem with fan starting up when car cold or warm . Did not matter if ignition was on or off . Easy fix. £13 . Locate external temp sensor. Replaced with new one and problem sorted. If this sensor is damaged or faulty the car assumes that the engine is too hot especially if it's a warm day or night. The management system cannot trace an external temp so assumes the worst scenario and engages the fan continuously. Hope this is helpful as it works for me. Have now fixed several octavia and passats since

I'm having a similar problem with the fan although it starts when the engine is cold and being started on. So, when there is +5 C or less the cooling fan starts when the engine is turned on! If I switch the engine off and start it again the fan does not start... If it is warmer outside, let's say between 5 and 15 when I turn on the ignition the fan starts and the ASR lamp is lit on the dashboard. In this case I have to switch it off and pull the key out for a couple of times to be able to start the engine without getting started the fan and ASR lamp... I already checked it with some diagnostical tool (VAGCOM) and it reported the temp. sensor's signal is intermitent, so provides false data. It was replaced but the issue remains. I also noticed on a warm the when the air temperature is above 15 C I don't have this error when coldstarting it. It makes sense to check the fuse box, might be there is some steam inside which gets condensed in cold???

I'm having a similar issue on my mk2 vRS, after 20 secs or so of the ignition being turned off the fans kick in at full speed which in turn is draining the battery. I do not have an issue with the temp readings on dash. I'm happy to check the sensors though having difficulty locating. Please help! getting bored of disconnecting battery each time. FYI code P068B shows

Edited 21 June, 20169 yr by leighm