Yamaha gauge trouble-need help...

New member to the forum and have to say that it is informative!! I just picked up a used Digital Speedometer. I hooked it up and the voltage reads .2 and the fuel bar just blinks the bottom bar. Any ideas??? Also if anyone would like to trade a like new Digital Tach +$(me) for a similar Digital Speedo(I need) let me know. Thanks in advance for the info and the first round's on me!!!

[boats.net]

Make sure you have red wire connected to 12 volt positive, yellow wire to 12 volts key on power, black wire to ground and white wire to pink fuel sender wire.

that's the way I have it?? I just disconnected the old gauge and put this one in it's place. It just flashes empty...

[boats.net]

To check the fuel gauge in tach, connect white wire on tach to ground(black wire) and gauge should go to full(with key on). If gauges doesn't read full then it's a bad gauge, if it does read full then you have a bad fuel sender in tank or bad wire going to tank sender.