You need to check that the code is correct , and how are you entering the code , because if the code is correct the red led will stay on , or come on then go out if the red led is flashing then the code is incorrect, and on older car you get a choice of two codes but only one of them is correct, try and phone a renault dealer with the chassi number and you plip key number and see if they will give you both codes , you might need to pop into the dealer because they might wont to see your log book as proof you have the vehicle.
mark
May 2008