Engine electronics light vectra 02?

Hi,

I have a vauxhall vectra 1.8 02, The engine electronics light has come on and when i turn the key there is little or no power. Is there anyway easy ways to solve this or do i have to take it to a garage. It has been on the diognostics for this fault before but was told it showed up to many faults to detect it so wiped computer and now it has done it again. Please help!!