There is only one state law regarding
U-turns, and it prohibits a U-turn if you cannot see 500
feet in front of you. At traffic lights a left turn signal
must be green or, if there is no left turn signal, then
the light for through traffic must be green. You must,
of course, always yield to oncoming traffic just as if
you were making a left turn. Some municipalities have
ordinances limiting U-turns.