Ford courier 1.8 diesel not starting, keeps blowing fuse?

Not starting at all,have changed the starting motor, battery fully charged, but when i turn the ignition it just blows the fuse in the external fusebox ( top fuse) narrowed it down to the voilet/orange wire, but dont know what this is for, it cranks over if i press the relay switch(with the casing off) but still not starting,it does not crank over from the ignition
Please help can not afford major work.