What the heck do these 3 wires do? -- Yamaha / Mercury Wiring Harness

[scjakester]

I have a Mercury wiring harness from a 2003 Mercury 4 stroke connected to a Yamaha 2004 4 stroke. It is running, the tilt/trim works and the key switch works, but what the heck do these three wires do? I have found several references but I have to (shamefully) admit that I am somewhat color blind.

 

[yamatech43]

Re: What the heck do these 3 wires do? -- Yamaha / Mercury Wiring Harness

Well, the blue on yamaha is for instrument lighting, the white is for kill circuit and white is sometimes also used for stopping oil transfer on 115 and 130's, don't know where harness came from but looks like that is what this one is....if i'm seeing two white wires and one of them connected. On the Mercury side the brown white is for trim sender to trim gauge and the tan is for water temp to gauge. Hope that helps.