w o w, where to start? it could be anything but start by unplugging and checking for corrosion adding electric safe grease then replugging all electrical connections. i cant tell you how often loose or bad connections cause problems.
next dont forget the kill switch which is another hidden gremlin that will drive you nuts if it or the wire leading to it has problems.
then look to the fuses, there are usually 3 of them on the wire harness and the manual will tell you where they are
seen here as part numbers 6a 12 and 18
http://www.suzukipartsnation.com/pag...004/5611840031
after that the post above covered all the components to look at