The switch just pulls out if you can get something under it, I used a small screw driver. Mines currently being held in with a pen lid, Renault wanted £33 for a new one. I've seen them on Ebay for £20ish though.
Dave
May 2008
the hazard switch is faulty you need to fit anew one they are not that much and the renault dealer might just have one in stock, but for the time being just disconnect the hazard switch and make sure the hazards are off when disconnecting.