I have a Yeti 2.0 140Hp Elegance with Climate Control and Air Conditioning.  For some time the heater blower fan has been switching itself on and off fairly frequently.  I can hear a relay clicking on and off down near the fan motor when this happens.  I have connected an LED to the power supply plug to the fan and can see that this is being interrupted and so I know it is not the fan motor.  When the fan is running the speed control all seems to work fine. Strangest thing is that when I turn the steering wheel to the right, the fan motor stops, and when I turn it to the left it starts.  I drive over quite bumpy roads and these have no affect and so I don't think it's a loose wire. Any ideas what the problem might be? Thanks.

This is a bit of a long shot, but I wonder if there is some unintentional coupling between the (high) current drawn by the power steering servo-motor and some part of the fan circuit ? The steering motor current direction will reverse depend on whether the assistance is one way or the other.  A problem with a shared earth contact is one possibility.  If this is true, then turning the steering with the weight off the front wheels (e.g. on a garage lift) would need little or no power assistance and the effect would disappear.

Thanks for the idea Austin 7.  What I forgot to say is that the problem is intermittent and I find that usually when I set off on a journey first thing then everything is OK for a few miles and then the problem starts again.  I can have a few trouble free months too and then suddenly the problem comes back for no reason.   I also notice that if I am stationary, generally the fan runs and as soon as I pull away it stops temporarily.  I have had the car from new (2011) and the problem didn't start until out of warranty unfortunately.  A real baffler.

 

Do you know where the relay is that I can hear clicking down near the fan motor?

I'd replace the relay and see how you go.

The relay is probably only activating because the current is being connected/disconnected elsewhere?

The relay is probably only activating because the current is being connected/disconnected elsewhere?

Sounds like a bad earth somewhere.

Sounds like a bad earth somewhere.

.... or a fractured wire making intermittent contact?

How old / what state is the battery? Low battery voltage throws up many and quite strange "faults"

.... or a fractured wire making intermittent contact?

Either way it's probably not good for the relay over time either.

Where is it parked o/night during the during winter I wonder.

How old / what state is the battery? Low battery voltage throws up many and quite strange "faults"

Agree

But that tends to throw up strange messages also.

Agree

But that tends to throw up strange messages also.

Sometimes - But not always, or so it seems........

Personally, the battery or a bad earth are the ones I would check first. Both are relatively easy to check..................Tony

Well after MSB Skoda at Darlington had told me they would have to remove the dash (4 hours at £92), find the fault and refix the dash (another 4 hours at £92) I decided to put up with it.  Then I noticed the plug on the bottom of the heater resistor module on the base of the blower would cause the fan to stop/start if moved.  I checked the plug wiring and it was ok so that led me to the resistor pack itself.  I bought a new one (£73.00), replaced it and everything is now OK. Glad I didn't let Skoda do it at a cost of £1000 +.

 

Thanks to everyone for your replies.