BMW E39 OUTSIDE TEMP. SENSOR

Hello everyone!!
I have a E39 (2001), the outside temperature display is reading over
100F all the time.. it all started after a rock hit under the car in
the area of the frotn right tire (dnt know if it has anything to do
with it..???) but after that moment the temp. is just way off.. does
anyone know where the temp. sensor is located? or what could be causing
this problem?? how to change if that was the case...
thanks for any help you can provide..
-Dan

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