Hi all i have a 2013 xt660z. I need help with these cables under seat .can i use one for power for satnav and grips. There is a 3 pin plug with red .black . yellow.
Cheers

If you're talking about the white 3 pin connector behind the battery, no, that is the plug for connecting the F1 diagnostic tool to adjust ECU settings and do diagnostics.
For heated grips I used power straight from the battery with inline fuse.
For a GPS or USB connection, I use the wire behind the dash cover just under the rev counter.

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2014 XT660Z - Barrett pipe, DNA stage1.5, Barkbuster hand guards and handlebars, Pivot pegs, Teknik suspension, Guard-it engine protector combo, B&B rear rack, Trax topbox.

I suggest that you put in a relay as well so that when you forget to turn off the heated grips you dont drain the battery. I use the wire behind the dash cover to trigger the relay (and drive the GPS) since there is only power when the bike is running (or on parking light - as i found out a day where i turned the key to far. Drained the battery with heated grips and aux light before i got back out 8 hours later.

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2011 Yamaha XT660Z ABS T�n�r�.

• Puig +8cm dark screen, Garmin Zumo 220, Scottoiler eSystem v2
• Barkbusters Storm with external weights, Noname 30mm bar risers & EzMoto alu. levers
• Kev's O2 Controller, Mccoi stepless controller with Hein Gericke heated grips
• TT +4cm seat, Pivot Pegs, Altech stainless sprocket cover