2007-2009 Yamaha F15/F20 Outboard Service Manual, Page 251Get this manual
Electrical system Engine start switch input voltage (reference data): Red (R) Ground 12 (battery voltage) 3Set the remote control lever to the neutral position4Check the engine start switch for continuity at the 10-pin main harness coupler (remote control box end)Check the wiring harness and neutral switch, or replace the engine start switch if out of specificationOFF ON START
3Check the engine start button for continuity between the engine start button connectors (engine start button end)Replace if out of specificationR
S6AG8180
Engine start button continuity: Red (R) Brown (Br) Button position Free Pushed Continuity No Yes