Green or blue — information only
Low beam headlights
The low beam is on. The lamp informs, it does not warn.
These lamps are not about a fault: they say a system is switched on, or remind you of something simple to do.
What to do now
- Nothing to do — it confirms the lights are on.
- ⚠️ If the symbol is lit but the headlights do not shine, the bulb itself has burnt out: the dashboard shows the voltage applied, not the light.
- Rules on when dipped beam is compulsory differ by country — check the ones where you drive.
- LED and xenon headlights are fed by a separate ballast. It fails no less often than the bulb and costs several times more — so the bulb is still checked first.
- A cloudy, yellowed lens takes away noticeably more light than it seems in the dark. Polishing brings part of it back without a single new part.
Codes usually behind it
The lamp only says that something is wrong. The code says what exactly — read it with an adapter and look it up here.
What to read next
A lamp is not a diagnosis. The same symbol lights up for a dozen different reasons, and only the code stored in the car tells them apart.
How the app helps
CarScan reads the codes behind the lamp through an OBD-II adapter, explains them in plain words and puts them into a report you can show to a mechanic.