BMW X3 Owners Manual > Displays: External temperature
If the indicator drops to
+37 ºF/+3 ºC
or lower, a signal
sounds.
A Check Control message is
displayed.
There is an increased risk of ice on roads.
Ice on roads
Even at temperatures above
+37 ºF/+3 ºC,
roads might be icy.
Therefore, drive carefully on bridges ...