Yahame fuel management to Garmin 3210

[Danny]

I have a 2001 Grady White Marlin 300 with twin Yahama 250 0X66"s. I need some help getting the Garmin 3210 to talk to the Yahama fuel management guage so it will read out the mpg. Which wires on the fuel management go to which wires on the Garmin 3210. Or will the fuel management talk to the Garmin so it could display the fuel mileage? Thanks in advance for any help.
Danny

[spearnreel]

FM+ (blue) to Garmin port 1 data out (blue) or port 2 (gray) if port 1 is in use
FM- (white) to Garmin ground (black)

[Danny]

I can't find a white wire coming from the fuel management gauge. I did see a white with red stripe i think. It seems like i read somewhere that there was a separate plug to buy for the gps interface.

[sandyda]

There is a lot of info on this at http://yamahaoutboardparts.com/index.php

[woolyt2]

it does not look like you have command link ...there is another plug that you have to get from the dealer to get the nmea in put.. take that back i dont think you can do that with that setup , only the speedo can get nmea ...not 100% sure but i think i am right

[Danny]

Actually Boats.net the Garmin GPS needs the output from the Yamaha FMS to tell you fuel burn per leg of a planned route, or just gallons per leg, miles per gallon or any other fuel/distance calculation you want. The Yamaha FMS figures GPH with a simple internal clock that runs anytime power is applied to the FMS system and measures fuelflow with it's inline sensor and divides that with it's internal clock and shows you GPH. You have to cut the little flat plug off and only use the white wire, tape or seal off the red and black wire. The white wire is the NMEA output lead that goes to the GPS. On my Garmin 235 the white wire is attached to the brown wire from the GPS and works fine. Hope this helps.

I'm going to try this............?? except I need to use the grey wire on the gps...........i think