Audi Repair: Audi: Exterior temperature sensor, temperature sensor, radiator

Question
In my 2001 A4 1.8T, the exterior temperature is incorrect and fluctuates wildly. The displayed value can be -30F when it is really 60F outside.
An annoying side-effect of this is that the AC starts heating up the interior when really low values are displayed. I always had this problem, but is happening more often now. The dealer replaced the temperature sensor twice, but the problem persists.

Answer
If the dealer really replaced the temperature sensor, then the problem has to be in the wiring.  I would check the connections to the temperature sensor (located just in front of the radiator) and also the wires to it for possible shorts or breakage.  WIggle the wire while someone observes the gauge to see if you can find the problem area.  Let me know,  Jan