В Онтарио:
Highway Traffic Act section 143:
U-turns prohibited
143. No driver or operator of a vehicle upon a highway shall turn the vehicle so as to proceed in the opposite direction when,
(a) upon a curve where traffic approaching the vehicle from either direction cannot be seen by the driver of the vehicle within a distance of 150 metres;
(b) on a railway crossing or within 30 metres of a railway crossing;
(c) upon an approach to or near the crest of a grade where the vehicle cannot be seen by the driver of another vehicle approaching from either direction within 150 metres; or
(d) within 150 metres of a bridge, viaduct or tunnel where the driver’s view is obstructed within such distance. R.S.O. 1990, c. H.8, s. 143.
Обратите внимание что про запрещенный знак ничего в этой статье не сказано. То есть, получается что если запретный знак есть то здесь все просто. Ну а если его нет, и соблюдены (a), (b), (c), (d), то можно делать u turn.
Highway Traffic Act section 143:
U-turns prohibited
143. No driver or operator of a vehicle upon a highway shall turn the vehicle so as to proceed in the opposite direction when,
(a) upon a curve where traffic approaching the vehicle from either direction cannot be seen by the driver of the vehicle within a distance of 150 metres;
(b) on a railway crossing or within 30 metres of a railway crossing;
(c) upon an approach to or near the crest of a grade where the vehicle cannot be seen by the driver of another vehicle approaching from either direction within 150 metres; or
(d) within 150 metres of a bridge, viaduct or tunnel where the driver’s view is obstructed within such distance. R.S.O. 1990, c. H.8, s. 143.
Обратите внимание что про запрещенный знак ничего в этой статье не сказано. То есть, получается что если запретный знак есть то здесь все просто. Ну а если его нет, и соблюдены (a), (b), (c), (d), то можно делать u turn.