citigo rad fan problem

Wig

Any advice welcome...
I can't go to a Skoda Forum, my browser won't let me.

Skoda Citigo, equal to VW Up or Seat Mii

The rad fan does not kick in when engine too hot. Usually not a problem as the engine, even in traffic will still sufficiently cool itself with the radiator. but in the hot weather in July that we had and stuck in traffic it did overheat...that's when I found out there was a problem. I have since then had no repeat of the problem, although I was a little concerned in the M5 Bank Holiday traffic queue experienced on the Aug 28th which was another hot day, so I turned the engine off regularly while waiting in that traffic.

I have now checked it,
I applied 12 volts directly to the fan...fan works.
Car stationary, I ran engine until it over heated, checked plug to fan for 12V when warning lights came on.... no 12 volts at the plug which feeds the fan.

I checked the fuse a couple of months ago, the first thing I checked and whilst it was difficult to find the apparent fan fuse, I believe I eventually found it and it was ok I think it had 12 volts on it. It was a while ago so here is a link
http://knigaproavto.ru/shemy/en/skoda/citigo/105-skoda-citigo-fuse-box-diagram.html

Fuse no 41. shared with brake pedal switch, which would seem to suggest that if pulled out the brake lights would not work? I probably tested this theory at the time.

If it does have 12 volts on the fuse and the fuse is ok... My question is...how does the fan kick in? i.e. if the fuse has 12 volts, then the switch for the fan must be between the fuse box and the fan...where would the switch be? and if the switch is the temp sensor, then we already know the temp sensor is working.


Ok.... my keen detective skills just kicked in
http://www.google.co.uk/search?hl=en-GB&source=hp&biw=&bih=&q=citigo+cooling+fan+switch

I think this is the the thing I saw right near the fan plug about 4 inches away in the bottom of the rad.... so that must be it....any way to test it apart from by replacement? And to change it without losing all the coolant?

How then does the overheating alarm go off...? There must be another sensor?

Similar but apparently not the same scenario
https://www.briskoda.net/forums/topic/254093-coolant-indicator-blinking/
(Yes I can just about read Briskoda but I cannot register or post there).
In this story, the car was apparently overheating, left idling at standstill, but he said he had the display saying 90C ..... I can't see how that had anything to do with the coolant expansion bottle????? I don't have the PID unit, so I can't see the actual temperature, but trust me, I know mine was too hot, because I was revving it on the driveway and it got very hot.



Thanks

forgotmyname

F41 Cooling fan for what?

F40 Radiator cooling fan....

But maybe the radiator is cold and the problem is your thermostat being seized or partially seized. So the engine is cooking yet the radiator is cold?

Also unless its a big fuse there will be a relay or other controller that will carry the larger load and a small fuse for the relay or controller.

Strider590

Fan switch is one possible, but if the car overheats when moving (???) then it's the thermostat jammed shut, this is what allows coolant into the radiator, no coolant going in, no fan switch activation.

Wig

forgotmyname wrote: »

F41 Cooling fan for what?

F40 Radiator cooling fan....

But maybe the radiator is cold and the problem is your thermostat being seized or partially seized. So the engine is cooking yet the radiator is cold?

Also unless its a big fuse there will be a relay or other controller that will carry the larger load and a small fuse for the relay or controller.

Oh yeah.... D'oh !

I will check later.

I did think last night after posting that there would be one sensor for temperature for fan to kick in, i.e. 95C and another sensor for the temperature to warn of overheating..i.e. 98C

Strider, it does not overheat while moving, indeed it also does not usually overheat when stationary, has to be particularly hot day and a hot engine before overheating when stationary. Not thermostat.

Thanks though..

ohreally

I'd go with the fan switch stuck in an open circuit condition (though it could also be a relay fault).

Wig

Today, is first time I've had some time to come back to this.

Rad fan switch connector was on the switch but not pushed on.

I bridged the connector...fan worked.

Pushed connector on properly, should be ok now, will check when I next take it for a drive.

Further confirmation of my suspicions that someone has done some work / repair to the front end of this car... The bonnet catch was loose when I bought it, and the bonnet is not perfectly flush with wing on driverside - about 1mm off. Apart from that I can't see any evidence of repair so I'm happy enough.

Also found VW "campaign 24A1" was a recall on these vehicles to have rad fan software and relay unit updated.... I might ask Skoda if this was done on my vehicle.

Thanks all.