Unintentional lane departure warning
System detecting unintentional crossing of a longitudinal road marking (solid or broken line).
Sensors, fitted under the front bumper, trigger a warning if the vehicle drifts (speed above 80 km/h).
The system works best on motorways and expressways.
The lane departure warning system can in no way replace the driver's vigilance and responsibility. Activation- Press button A, the indicator lamp comes on.
- Press button A again, the indicator lamp goes off.
The system status is retained when the ignition is switched off.

Lane departure warning Detection
You are alerted by vibration of the driver's seat cushion:
- on the right side, if the road marking is crossed on the right,
- on the left side, if the road marking is crossed on the left.
No alert is given while the turn indicator is activated and for approximately 20 seconds after it is switched off.
A warning may be issued when crossing a direction marking (arrow) or a non-standard marking (graffiti).
Operating faultIn the event of a fault, the service warning lamp comes on, accompanied by a warning tone and a message on the multifunction display.
Consult a CITROËN dealer.
Detection may be impaired:- if the sensors are dirty (mud, snow, ...),
- if the road markings are worn,
- if the road markings and road surface have low contrast.
Test yourself
A quick Citroen C5 quiz: every answer comes with an explanation and a link to the manual page.