Yamaha YZ 2018 Series Owner's Service Manual page 315

SIGNALING SYSTEM
1. Joint connector
2. Joint connector
3. Joint connector
6. Main relay
8. Battery
9. Frame ground
10.Starter relay
11.Main fuse
14.Warning light
16.Fuel level warning light
17.Resistor
18.Fuel sender
21.ECU (engine control unit)
29.Joint connector
41.Frame ground
43.Negative battery lead
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