See also:

Passenger safety
Seat belts and front passenger's airbag The seat belt fastened/unfastened status for each seat category is indicated by the lighting or flashing of the warning lamps linked to each position: ...

Replacing bulbs
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Operating fault
If this warning lamp comes on, accompanied by an audible signal and a message on the multifunction screen, this indicates a malfunction of these systems. Have the systems checked by a CITRO&Eu ...