I dis-connected the battery for about 15 minutes, re-connected it and then the FIRST thing I did was try the lock-to-lock procedure with the steering wheel. No change, light still on.
I'll pull the brake switch out next, but is there a way to test the switch before buying a new one??
Continuity?? Certain ohm reading?? Is it worth spraying some contact cleaner in to it, or is that going to do even MORE damage??

Thanks for all your help Gilly.

__________________
Barry