Cartronix---- Dash Instrument Cluster Repairs

Hi, I have a 2004 Auto Arapaho which has developed a strange fault and I would ask if you could shine any light on my problem. My dash lights do not come on when the ign key is turned for starting, no head lights, and no cab window operation. The only amber light to show on the dash is the water in fuel light. But when turning the ign key the engine starts and runs normally. Windows and head lights still do not work. An auto electrician took the drivers door window switch assy out from its position and connected an aux feed to the blue and white cable which brought it all back to life. Trouble is that’s as far as he could go and suggested there was a relay hanging up somewhere in the system. I would appreciate your thoughts on my problem and any suggestions for rectification.
kind regards
peter Ward.( peter_jennyward@hotmail.com)