Flashing Yellow Light for Special Caution
The signal indicates special caution
When You See This Sign
When you come to a location where a yellow flashing light is displayed, you should immediately reduce your speed and increase your alertness. Improve your observation of any pedestrians, cyclists or vehicles, and continue only when you are sure it is safe to do so.
Rules & Regulations
- A yellow flashing light indicates that you must show particular caution — it means you must adjust your speed and be prepared to stop if necessary.
- The signal itself does not create an automatic duty to yield or to stop; you still have to follow the usual right-of-way rules and road markings at the location.
- When a yellow flashing light is used instead of the regular traffic signals (for example during a malfunction or temporary arrangements), you should follow road signs and general principles of caution.
- You must not continue driving if doing so would endanger other road users or vulnerable road users — stop when the situation requires it.
Tips for Drivers
- Slow down early and scan the road ahead, to the sides and at crosswalks — do not assume you have a clear path.
- Be extra attentive to pedestrians and cyclists who may cross unexpectedly; be prepared to let them pass even if you would normally have priority.
- If the signal is flashing at an intersection, check the road signs and the normal right-of-way rule before entering the intersection.
- In poor visibility or heavy traffic: be more cautious and let other vehicles pass if it reduces the risk of conflict.
Common Mistakes
- Believing that flashing yellow means priority or 'green light' — it does not give the right to assume free passage.
- Ignoring the signal because it is not red or green; many learners underestimate the need to slow down.
Test Yourself
Road Sign: Flashing Yellow Light for Special Caution
What should you be aware of here?
- A Take extra care and be particularly alert.
- B You must stop before proceeding.
- C The signal indicates that a green light is coming soon.
- D It is a warning of falling rocks.
Exam Tip
On the theory test you may get a statement question testing whether flashing yellow creates a duty to yield or to stop — the correct answer is that it requires caution and adjusted speed but does not automatically create a duty to yield or to stop by itself.
Did You Know?
The code name for this signal in the Swedish Transport Administration's sign register is SIG18 and it is often used for temporary hazards, road works, or where regular traffic signals are out of order to indicate the need for particular caution.
Frequently Asked Questions
Do I have to stop when I see a yellow flashing light?
No, you do not always have to stop. You should adjust your speed and be prepared to stop if the situation requires it, for example if someone steps into the road or you cannot pass without danger.
Does the signal apply at all times?
Yes — when the light is flashing, the message of the signal applies regardless of the time of day. The flashing is intentional to draw road users' attention to the need for particular caution.
Is flashing yellow always used at road works?
Not always, but it is common at road works or temporary traffic arrangements to indicate that road users should be extra attentive. Placement and meaning can be supplemented with road signs.
Can I rely on other road users to understand and follow the signal?
You should not rely on that — act defensively. Others may make mistakes or fail to brake in time, so keep your distance and be prepared to intervene to avoid a collision.
Practice more in the app
Study Swedish road signs and driving theory in English. 314 signs with rules, tips and quizzes.