Thanks Richard, it's a Feb.2013 but built in Dec 2012 so like you say will be the 12 pin variety. I did think about upping the fuse size to 7.5 amp but then thought it must be 5 amp for a reason so left it at that as I didn't want to cause any more problems.
The 2 diodes that you mention would they be inside the steering column shroud or buried in the back of the dashboard.
