Millions of drivers could be putting themselves, fellow motorists and pedestrians at risk because they do not know The Highway Code, a survey has revealed.
One in six drivers have ignored road signs when they do not know what they mean, Goodyear's Test the Nation survey found.
More than four in 10 (44%) drivers could not correctly identify that a red and amber traffic light shown together meant stop, Goodyear's Test the Nation survey found.
Instead they thought it meant to proceed with caution.
The study tested 2,000 drivers on road rules and signs and found that while almost half rated their knowledge of the Highway Code as good or very good, that was not the case.
Almost three out of 10 did not think it was necessary to stop if a pedestrian was at a zebra crossing waiting to cross, while more than a quarter did not know the speed limit in a built up area is 30mph.
More than a quarter failed to correctly identify the no right turn sign. One in seven thought the sign meant the road up ahead on the right was closed.
The survey also found that almost a third of all drivers failed their theory test at least once, while more than a quarter have been involved in a motor vehicle accident as a driver since getting their licence.