The answer options
- Leave them on, it may become foggy again
- Turn them off whilst visibility remains goodCorrect
- Flash to warn oncoming traffic of the fog
- Leave them on if others do too
Why the other options are wrong
- “Leave them on, it may become foggy again” is a distractor. It does not meet the standard the question is testing, which turn them off whilst visibility remains good 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.
- “Flash to warn oncoming traffic of the fog” is a distractor. It does not meet the standard the question is testing, which turn them off whilst visibility remains good 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.
- “Leave them on if others do too” is a distractor. It does not meet the standard the question is testing, which turn them off whilst visibility remains good 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 switch off your fog lights as soon as visibility improves. Leaving them on when the road is clear is illegal because high-intensity lights dazzle other road users and can obscure your brake lights. Flashing your fog lights or keeping them on just because other drivers do is unsafe. The Highway Code states you must only use fog lights when visibility is seriously reduced, which generally means 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.
More vehicle handling questions
- A lot of snow has fallen recently. When driving in these conditions, what are some things to think about?
- After fog has cleared, it can be dangerous to leave your rear fog lights switched on. What is the reason for this?
- What colour are the reflective studs along the left-hand edge of the motorway?
- During the day, when should dipped headlight be used?
- How can you regulate your speed with the engine of your car?
- How should you deal with this hazard?