Actually, I think in the 206 the light switch is somewhere in the passenger footwell as the car was designed to be a left hand drive and was then modified to right hand drive for this country amongst others.
My friend has a 206 which had the same problem and took it to a peugeot dealer who didn;t even charge him for the repair as apparantely it's a common problem - a passenger you've had must have inadvertently kicked the switch