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    What must you do when visibility improves after driving in fog?

    DVSA-style practice question · Vehicle Handling

    The answer options

    • Leave your fog lights on in case visibility decreases again
    • Turn off your fog lightsCorrect
    • Keep your front fog lights on
    • Keep your rear lights on

    Why the other options are wrong

    • “Leave your fog lights on in case visibility decreases again” is a distractor. It does not meet the standard the question is testing, which turn off your fog lights does. Picking it in the real test costs a mark you cannot get back, and with a pass mark of 43 out of 50 you only have seven to spare.
    • “Keep your front fog lights on” is a distractor. It does not meet the standard the question is testing, which turn off your fog lights does. Picking it in the real test costs a mark you cannot get back, and with a pass mark of 43 out of 50 you only have seven to spare.
    • “Keep your rear lights on” is a distractor. It does not meet the standard the question is testing, which turn off your fog lights does. Picking it in the real test costs a mark you cannot get back, and with a pass mark of 43 out of 50 you only have seven to spare.

    Why that is the answer

    You must turn off your fog lights as soon as visibility improves. High-intensity fog lights are very bright and can dazzle other drivers, especially those travelling behind you. They can also obscure your brake lights, making it harder for following drivers to see when you are slowing down. The Highway Code states you must only use fog lights when visibility is seriously reduced to less than 100 metres.

    What vehicle handling covers

    • · Front and rear fog lights and the 100-metre visibility rule
    • · Descending steep hills in a lower gear and engine braking
    • · Traffic calming, humps, and driving over tram rails
    • · Night driving, dipped headlights and dazzle from oncoming traffic

    Mistakes learners repeat on this topic

    • · Leaving rear fog lights on after visibility improves
    • · Coasting downhill in neutral to save fuel
    • · Using full beam on a lit motorway or behind another vehicle
    • · Accelerating between speed humps instead of holding a steady speed

    Instructor tip: Any question with fog in it usually turns on the 100-metre rule — check visibility before you check the lights.

    How this comes up in the real test

    Questions from vehicle handling appear throughout the 50-question multiple-choice section, and the wording changes between versions. Learn the rule rather than the sentence: the DVSA can ask the same point from the opposite direction, and a memorised answer falls over the moment the phrasing moves.

    The pass mark is 43 out of 50, so seven wrong answers is your entire margin. If a whole category is shaky, run the topic practice below until you are getting every question right for the right reason, then go back to full mocks under the clock.

    Practise Vehicle HandlingSit a full mock test

    More vehicle handling questions

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