Lighting and Optical Signals
After driving through a stretch of dense fog with the rear fog light on, visibility improves. What should you do?
Reviewed on 26 Jul 2026
- A Keep it on for safety
- ✓ Switch it off so as not to dazzle those behind
- C Also switch on the front fog light
- D Switch to main beam
Why this is the correct answer
You must switch off the rear fog light as soon as visibility improves, since its high intensity dazzles and annoys the drivers behind once it is no longer needed.
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