Heater Problem A4

Wondered if anyone can identify this problem, before I take it to the dealer.
I have a A4 B6 1.8T Q and for some reason the blower will not work when the
temp is below 8c, as soon as the temp goes above 8c it works fine lol.
This is a well strange problem, the heat blows out fine under its own steam on the motorway when its like -2c but the fans will not come on, the water temp is perfect at 90c and the header tank is at the correct level.
The interior climate control shows full speed on the fan blower but they do not come on, is there some sort of sensor within the car that senses a temp somewhere and tells the blowers to come on/off
Another weird thing, in the summer or at any temp where the blowers work, when you put the wipers on, the blower speeds up for a few secs and then goes back to normal, it's as if the sensor on the dash gets momentarily confused by the wiper sweep and speeds up the fans.
Anyone any ideas before it goes into the dealers?
Cheers
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The climate control is set up to not allow the AC to turn on if the outside temp is 8C (or very close to that). It is not supposed to affect the fan.
There is another system that will not allow the fans to turn on until the engine coolant temp reaches a certain level so that the heater doesn't blow cold air.
It sounds like either the wiring for these two systems is incorrect or that the programing in the climate control is bad. Either way the dealer is the best place to sort this out especially if you are still under warranty.
Ronny wrote:

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Cheers tony, do you think a wire may have just come off? and if so where abouts.
Its only happened recently
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It might be related to a faulty ground but I would not be able to guess where that might be.
Ronny wrote:

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"Ronny" wrote

Any fault codes stored in the ECU? I'm guessing you would have told us if there were, or if you had access to a VAG-COM tool, though. :)
Pete
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No fault codes, nothing :(
I got VAG-COM
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