sounds stupid i know but have you checked all the fuses?

are the dash lights coming on when you turn the key?

if you look in the enginebay part of the engine loom will clip into the car loom, the plug with have 7 wires (iirc) going through it, disconnect the plug and check that the red wire is live, also check the black and the black/green wire are live when you put the ignition on.

sounds like a power feed problem, ie fuse etc. either than or the ecus wankered. check the above though.