Does the sign on this board inform you of a place on the road where there is, or there might be a danger?

In the photo, near a bridge, there is an electronic board with the words "Jedź ostrożnie" (drive carefully), the air and road surface temperature and a lit warning triangle with a car going into a skid - the equivalent of sign A-15 "slippery road". A sign shown on the board warns of danger in the same way as an ordinary metal sign. The answer is: yes.

The Regulation on road signs and signals states that road signs also exist in the form of illuminated signs, and warning signs warn of places where there is or may be danger, and require you to exercise particular caution. On a bridge the road surface cools down faster, and in the rain it is easy to skid, so you slow down and avoid sudden movements of the steering wheel.

Legal basis: § 1 para. 3 point 1, § 3 para. 1 and § 7 para. 6 of the Regulation on road signs and signals