Fuel Gauge Not Working

[Bama J]

New member here, so hello everybody. I have recently became a pontoon owner for the first time, and have purchased a 1999 Fisher Freedom DLX 200 Pontoon. The last time out, my fuel gauge stopped working all of a sudden. When we were on the way back to the boat ramp, it did flicker a few times and showed the correct reading, but it was only for a second or two then it went back to empty.

I began troubleshooting by looking at the wires at the sender end, the connections looked a little funky so i replaced the connectors on both the wires with new and cleaned them. I then put an ohmmeter across the connector of the pink wire and the ground wire while they were connected to the sender and it read about 95 ohms, which is about right because I should have between 1/2 and 3/4 of a tank of fuel. I even rocked the boat a little and the ohms flunctuated as the fuel sloshed around, so if I did this right, I think the sender is good.

I chased the wire to the dashboard, I can see it all the way and it looks fine. I tested the guage by running a jumper wire from the S post to the ground post, and the guage went to full. So it appears the guage is good. For good measure, I also replaced the connectors on the guage end, even though they looked fine. All my other gauges work fine, and they are grounded in series, and the fuel gauge is actually the middle on of the three, so it doesn't seem to be a bad ground. Also, voltmeter shows 12v going to the gauge when the key is on, so it's getting power.

So, if the gauge is good, the sender is good, and the wiring looks fine, what's left? I'm stumped here.

[cwag911]

Welcome Bama J. You didn't mention if you grounded the wire from the sending unit to the guage at the sending unit end. It should peg the guage and if not, I would check that the sender is grounded properly.

[Bama J]

Ok, thanks. I did not. I will try that tonight.

[dockholiday]

Don't know how to fix your problem just wanted to say hello, and WELCOME.
doc

[crankshop1000]

The ground wire to the tank is probably your problem.