Renault megane instrument panel dead!?

I have a X reg. 2001 model 1.6 megane. i haven't used to car for afew months and the battery died. I charged the battery and the car started and everything working but the battery was shoot. I got a new battery a the car starts fine but the speedo/rev counter don't work, the rest to the panel is fine. I've checked all the fuses. Can anyone help?