 RE: Yamaha fuel gauge always reads full??
Bill,
One tank? Are these Command Link gauges or the standard Yamaha digital multi-function?
If it has always done this it could be one of two things. Either the fuel sender in the tank is physically stuck in the up position or the dip switch setting on the Yamaha Speedo are set incorrectly for the ohm values for the sender.
What I would do is take the sender out of the tank, and manually raise and lower the float. See if it has any effect on the gauge. If it does not, I would try changing the dips for the gauge to another sender value. Again raising and lowering the float to check the movement ofthe gauge. Unlike standard gauges the speedo'sfuel gauge is somewhat slow in reacting. So with every movement of the float wait a few seconds for the gauge to change.
Since the gauge says full, the white wire sender wire on the gauge is connected to something. If it was not, it would flash empty all of the time.
Andy | 
