Brake light not working - front only

[Fazerider]

When that happened to me it was caused by corrosion to one of the wires at the little spade terminals that plug onto the switch. It was a fiddly job remaking the end by cleaning up the spade connector and soldering the wire back on... crimping a fresh terminal on would have been an easier solution if I could have been bothered to go out and buy a kit. :lol