megane 1.5dci electronic fault?

renault megane 1.5 dci 2004. on dash it says electronic fault,sometime speedo works sometimes it doesnt.only 1 of my widows work all the fuses are intact.ive heard the seals on the doors are no good and i think thats why the drivers window doesnt work,water has got into motor.ny help on the speedo thing plus other window faults ?