1991-1993 Yamaha Exciter II-570 Service Manual, Page 386Get this manual
ELECTRICAL STARTING SYSTEM
FAULTY Check the main switch, fuse and rectifier_ _
Correct connection
Replace the main switch, fuse and or rectifier
MAIN SWITCH (FOR ELECTRIC MODEL)
1Disconnect: Main switch coupler CD 2Connect: Pocket Tester (90890-03112, YU-03112) (to main switch coupler)