renualt Magena 1.9 dci 2007?

I hae renault 1.9 dci.
Jus recently, Ihave had a fult with my main head light unit. Each tie I stat my car, the sidelights go on, but cannot turn of, th lightsstalk is ok an the main headlights and fog light come onand can turn off, but theside lightremain on when engine is running. cannot turn off even when the engine is turn off, side light remain on. Can any one tell me wha he fault is an ca I fit th fault ok?