Hey...i had this problem and have cured it. my 04 scenic have a factory fit cd player under the passenger seat> You will need to remove the compartment door from under the front passenger seat. Nestled at the bottom is a fuse board with a relay. Check all the fuses...from memory its a 10amp fuse. Sadly there are a few 10amp fuses on the board and its a matter of checking. found a blown fuse and replaced it. Light and powersocket working fine albeit the lite has a seperate fuse/supply to that of the power socket. Hope this helps you. forgot to mention...if you have no cd player then remove the tray completely...dead simple. Then there is ample room to stick yr hand in. With a cd player room is very limited and I ahd to use long nose pliers as no room for my finngers/hand.
Nice one Markieboy
For underseat tray removal click on the link below
Renault Scenic II - Removal of Underseat Storage Trays with Pic's