citroen relay non runner?

[aquatic_man2000]

i have a 2004 citroen relay in the workshop that came in as a non runner, after scanning it there are multiple codes including double relay, egr, rev/timing syncro, fuel pre heater curcuit. the ecu was sent and tested by the garage that had the van before it came to us and got a clean bill of health. the 80 amp fuse on the battery was blown, the heater unit on the breather pipe was blowing the fuel fuse so changed that, had it running twice but very badly. also found that the purple power wire from the fuse box to the ecu drops to 1 volt with ignition on. also 2 relays are making strange noises if you plug the egr solonoids in and out??? any ideas? im suspecting the fuse box?