Not an easy answer BMWs tend to have problems with connections at at electrical junctions, although less than most bikes of this age.What most owners do to overcome this, is to virtually undo every connector clean with Deoxit, or any good contact cleaner.Those magnifying glasses are really good when inspecting.If it is really bad or you have green verdigris you can scrape clean with a small screwdriver or something similar don't be too heavy handed, be gentle. Then lubricate with a very small amount of dielectric grease or Copper Cote you don't need a lot, apply sparingly with with a toothpick or cocktail stick.You will need to remove the fuel tank,and it is a good idea to go over the whole electrical system from one end to the other ,I know this sounds painful and overkill but it will save you problems in the future, no one likes been stuck in the middle of nowhere with an electrical problem.I should only take you a day and you can get to bond with your bike, it can be very therapeutic. You don't have to be an electrical genius to to this just go slowly and be thorough.If you have problems remembering which connector you have done mark with a piece of tape, remove all the tape when you have finished and have a couple of beers.Any time you work on your electrical system check, clean and lube the connector before reconnecting.
Regards Martin :2thumbup: