Special Warning Device
The device warns of a specific danger
When You See This Sign
When you encounter the Special Warning Device sign you should immediately be alert, reduce your speed and read the device's signals or supplementary plates. Follow what the device shows — be prepared to stop or change your driving if required.
Rules & Regulations
- The sign indicates that a special warning device is present to alert you to a specific hazard; you must notice and take the device into account.
- You must obey the device's signals and instructions (e.g., flashing lights, audible signals, or text messages) when it is active.
- The sign itself does not impose a speed limit or a duty to stop — follow the applicable speed limit or any supplementary instructions.
- Adjust your speed and distance and be prepared to stop if the warning device requires it or if the traffic situation demands.
Tips for Drivers
- Slow down in good time and look for what the device is warning about (flashing lights, sounds, information panels, or supplementary plates).
- Always follow the active signals — if the device shows stop or a red light, stop and wait for a clear signal before you continue.
- Be especially attentive to vulnerable road users and vehicles that may brake or change direction when the warning is activated.
- In poor visibility or night driving, use extra caution and keep a longer distance because the device's signals may be harder to perceive.
Common Mistakes
- Assuming the sign always indicates a specific hazard (e.g., a speed bump) instead of checking which device or text is actually warning.
- Assuming the sign automatically means a reduced speed limit — it does not, without a separate speed sign or message.
- Ignoring the device when it is active because it looks unusual or temporary.
Test Yourself
Road Sign: Special Warning Device
What does this special warning device mean for your driving?
- A It warns of a particular danger not covered by regular warning signs and you should be extra alert.
- B It indicates that you have priority at the next intersection.
- C It marks a parking area for emergency vehicles.
- D It indicates that the road is one-way.
Exam Tip
On the driving theory test they may check whether you know that the sign itself does not change the speed limit — it requires you to notice and follow the active device's signals or supplementary signage. Read carefully whether the device is active or which supplementary plates are present.
Did You Know?
Sign X6 is used when a specific, often active warning device is needed and is relatively uncommon compared with ordinary warning signs. It is often seen in combination with supplementary plates or electronic messages that explain the hazard (e.g., school route, level warning on a bridge, or a temporary warning at roadworks).
Frequently Asked Questions
Does the sign mean I must always stop?
No, the sign does not automatically mean stop. You must follow the device's signals — stop only if the device or supplementary signage explicitly requires it.
Does the warning apply only when the device is activated, or always?
The sign indicates that a special warning device is in place, but its active signals (flashing, sound, text) determine when you should act. Still be vigilant even when it is not activated.
Does the sign mean the speed is reduced?
The sign itself does not change the speed limit. If the speed is reduced it will be indicated with a separate speed sign or communicated by the active device.
Where is this sign most commonly seen in Sweden?
It is used at locations where technical or temporary warning devices are needed, for example at schools with active warnings, certain railway crossings, bridges with level warnings, or at roadworks.
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