Yamaha Fuel Management-- No MPG

[Frank C.]

Have a new boat with twin 2005 F200's. All of my gauges are functioning properly except for the MPG on the FMG. The gauge reads 0.0mpg and never moves from there. i'm thinking that maybe the pin is set for a GPS readout instead of speedo. Any ideas?
How would I be able to hook up the FMG to my GPS. I wasn't proveded with any wiring diagrams.
Thanks

[jb123]

its been a while since i hooked up my system but i think theres a wired link between speed and fm gauge to calculate mpg

[Frank C.]

There is a 3 pin connector going between the speedo and the FM. I have that connected, but still get no readout other than 0.0mpg. I tried reconnecting it, but haven't had a chance to take the boat out since. Hopefully it was a bad connection. The only other thing I can think of, is that the pins are in the wrong position. That's my next step. Any other suggestions would be appreciated.