Remove the steering column top cover by undoing the two screws (its the square-ish cover that fits above the indicator/wiper stalks) and check that the black wire is attached to the spade connector (I bet it has snapped
) that comes through the steering wheel bracket. If this is where the problem is let me know and I'll post pics of my fix.
.....two weeks is how long it took me to figure out where the fault was........