Indesit IDL 40 light 4 flashing ?

Hi all

we have an Indesit IDL40 which has been in use with us since march 2008 but owned since Aug 2006. During the final cycle of a wash programme when it should be drying the No.4 Light, drying cycle, flashes now as opposed to staying on throught out the cycle before. Also i'm not convinced that the rinse aid is dispensing. Help please before i seek the assistance of Mr H. Ammer.

Please note it is only the No.4 flashing not the No.2 and No.4.

Many Thanks, Wayne.