When I opened mine up I couldn't see any damp.
It is a known fault on Renaults and worth doing if you can.
UNLESS of course it is a problem that Renault have dealt with on newer cars, mine is a 1995.
An auto sparks should be able to do it if you can't.
Be careful when opening your key fob. Mine has contacts to the bulb that are easily breakable. If you do break the contacts they can be soldered back into place.
The wonders of modern science eh?
PS Just found this on another thread
If they are ok then check the base of the arial. This is a common area for leaks, to cure remove the centre console, pop out the courtesy light, IR reciever & sunroof controls and you'll see the torcx head screws that hold the console in place. Undo and put to one side and the console drops out. This gives access to the arial mounting bolt, undo and remove the arial and clean the roof around the arial hole. apply a thinish layer of clear bath sealant and refit the arial and console.