picasso 2.0 sx hdi ?

display shows battery warning light on. multiple items not working i.e display shows total mileage but has stopped recording new mileage.fuel guage not working ,speedo not working, washers /wipers not working,front fogs not working,heater not working,indicators not working. but radio is,lights are,clock is,hazards are,central locking is,horn is, and engine function appears ok so my question is : is this likely to be an ECU fault or a BSI FAULT?