Engine cooling fan ceased functioning

[Sampolainen]

I arrived at my parking lot the other day and stepped out of the car, left the engine running, no A/C. I had the driver's door open and as I was conducting my business I heard the notice gong go off. I thought it was the low gas warning since it was running low already and so didn't pay any attion to it. A few moments later the gong sound came again, this time continuous. :confused:

I hadn't heard that before so I jumped in the car to see what's it about and noticed the lit temperature warning and the temp. meter almost reaching the red zone. I turned the heat up and blower to the max and the temp gauge stopped rising. I noticed there was no fan noise when obviously there should've been so I took off and sure enough, as soon as I had driven around 400m @ 60kmh temp gauge back to 90 and all was well.

I gather that since the temp dropped down right after I started moving the thermostat should work, right? Also, hot air is coming from the heater if needed. No other problems than overheating after some time standing still with engine running. I've tried to search the forum for info on cooling fans but haven't found a lot so it doesn't seem to be a common failure point. I'll gun it this morning going home from work so I get to see if high speed highway cruising will lift the temp.

On a side note, the smaller AC fan does work as I tested it, even without the engine running if I push the AC button the fan turns on. Should the larger fan turn on as well? As I did some tests I noticed that after the temp rises above 90c the car automatically turns off the AC, the smaller fan still keeps running though.

How should I start checking what has failed and where? I already checked all the fuses on the drivers side panel and the three that are with the battery. Are there any more? And also it's not mentioned in the manual which fuse if for the radiator fan. Where can I find the relays? I appreciate any help you guys can give

Edit: I've changed the temperature sender about 3 months ago, could this have had an effect like this? Also, the larger fan rotates freely, no jamming.

Edited 2 July, 2009 by Sampolainen

[Sampolainen]

I just arrived home from work. Around 15km on the highway, first I did around 5km in 3rd gear about 95kmh. Then I increased speed to 115kmh and nearly 5000rpm and like I guessed, no change in temperature . This would rule out waterpump failure, yes? Besidees, it shouldn't fail quite yet, only done 35000km on it.

[Sampolainen]

I found out that some relays are under the steering wheel. Does anybody have a list of what does which one control? Apparenty 'relay 109' is the main relay... And any info on the fuse# for the fan? This I couldn't find out yet. It's got to have a fuse, right? It should consume quite a lot of power to run it

What controls the fan spinning? Does it have an independent module built in and a sensor that connects to watertemp? Or is it just a dumb fan that gets turned on by some electronics? Any info/tips greatly appreciated!

[Sampolainen]

Some progress then as I have had time to fiddle around with the car. The fan itself works, I connected it directly to the battery. BTW I found out that there are two different kind of fans, single and double speed, mine's single. Now apparently these fans are controllod by a fan control module, located under the battery. This module also contains the relays I've been searching for. Fuse for the fans is supposedly located on top of the battery, I'll have to check those out properly as well.

Ahh... I guess it's time to dig in to the battery compartment then :ashamed:

Update

After quite some digging, I have not managed to find any kind of control unit under the battery. Unless it is under the frame beam? Anyways, I found a connector that was corroded so that one lead had snapped off. It's a red one going to the temperature sender in the radiator and it splices to a relay next to the battery. If this wire is supposed to supply power to the sender and it's broken then it's no wonder the fan isn't working. I'll fix this tomorrow since I don't have my stuff here at work. I hope this solves the problem

Second update

Well I forgot to take me gear with me to work :< I packed it up and all but then left it home, not too smart :(

So no repairs today. Another try tomorrow

Edited 11 July, 2009 by Sampolainen
oopsie + update

[Sampolainen]

It has been fixed now. I hope this helps somebody if they have a similar problem

[Alex2x]

Some progress then as I have had time to fiddle around with the car. The fan itself works, I connected it directly to the battery. BTW I found out that there are two different kind of fans, single and double speed, mine's single. Now apparently these fans are controllod by a fan control module, located under the battery. This module also contains the relays I've been searching for. Fuse for the fans is supposedly located on top of the battery, I'll have to check those out properly as well.

Ahh... I guess it's time to dig in to the battery compartment then :ashamed:

Update

After quite some digging, I have not managed to find any kind of control unit under the battery. Unless it is under the frame beam? Anyways, I found a connector that was corroded so that one lead had snapped off. It's a red one going to the temperature sender in the radiator and it splices to a relay next to the battery. If this wire is supposed to supply power to the sender and it's broken then it's no wonder the fan isn't working. I'll fix this tomorrow since I don't have my stuff here at work. I hope this solves the problem

Second update

Well I forgot to take me gear with me to work :< I packed it up and all but then left it home, not too smart :(

So no repairs today. Another try tomorrow

Having a siimilar problem the radiator fan comes on and wont go off, and it flattens the battery, went to skoda they said its the control reley unit that needs replaced and quoted erm £360, I nearly fell over , so I'm trying to find ethier a fuse for the thing or where the reley for the fan is located did you ever find the fuse.

[Turbo_Boss]

[Turbo_Boss]

Update

After quite some digging, I have not managed to find any kind of control unit under the battery. Unless it is under the frame beam? Anyways, I found a connector that was corroded so that one lead had snapped off. It's a red one going to the temperature sender in the radiator and it splices to a relay next to the battery. If this wire is supposed to supply power to the sender and it's broken then it's no wonder the fan isn't working. I'll fix this tomorrow since I don't have my stuff here at work. I hope this solves the problem

Hey Sampolainen, thank you for sharing your fix solution. Here are some pics of the Fan Control Unit under the battery. Maybe you can point us what conector was the fault one.

THX,

Isaac

Edited 9 January, 2010 by Turbo_Boss

[Turbo_Boss]

Having a siimilar problem the radiator fan comes on and wont go off, and it flattens the battery, went to skoda they said its the control reley unit that needs replaced and quoted erm £360, I nearly fell over , so I'm trying to find ethier a fuse for the thing or where the reley for the fan is located did you ever find the fuse.

Alex, if the the fan comes on and wont go offf, I dont think your problem is a fuse. BUT, that fuse is located on top of the battery. Usually you will find there 3 green fuses.

If you check your fuses and they are OK, I recomend you to check the Fan control Unit under the battery. Please refer to the pics I post above.

In order to remove it, I recomend you to take out the 12V battery. There are 2 screws that keep the Fan control Unit.

Keep in mind that this Fan Control Unit is under the battery sitting very low and it can get water inside and maybe this is why is not working properly.

Remove the Fan Control Unit and open it. You will find a relay inside and a small electronic circuit. Check is there is not sign of water inside...... Usually you will see some white residue. If there is water residue, clean it with Contact Cleaner Spray. Also check the relay to see if it not damage and is sticket in the close position allowing the fan to continue run without stoping.

I help a friend with a Fan Control Unit that was not working OK. After open it there was sign of hard water (Like a white dust), we clean it and seal the case with silicone glue in order that water dont get in again...... I never took pictures of this fix........... Shame on me :'(

If you open it, please take pics in order to share them with us.

Good luck,

Isaac

Edited 9 January, 2010 by Turbo_Boss

[adbru]

Hi,

Update to this thread as I have a similar problem with my 2004 (new shape) 1.9tdi classic.

After speaking to the dealers it seems my car does not have the unit under the battery (no wonder I couldnt find it !! ) but has it built into the fan itself.

Part number 1K0959455CP quoted at £126 + vat.

Now saving up to get the part, the fan fuse has been sitting in the ashtray since new year when the battery went flat !!

hth

Adbru