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Ok, so the fuel gauge has never worked right...pegged to full with the lights on, jumped all over the place with the turn signal on. Read old posts, seemed to be a bad ground, right? Took the gauge out expecting to find three connections, power, ground and sending unit....out came the gauge, two 24v wires to the power, one purple (sending unit) going to what looks like should be the ground ( G in casing of gauge on right, + sign on left) the spade connectors on each side are the gauge light....what am I missing? Thanks!

The spade connectors are for the ground of the gauge and light. The gauge light goes into the top hole and has it's own connector on it - +24V.

You should also make sure the sending unit is well grounded.
Ground is at the unit under the access cover.

You could also test the resistance value to make sure the sender is OK.
When FULL it should read ~2.2 Ohms, when low, below the reserve level
the max resistance is 84 Ohms. If you know where your level is you can
take a rough guess on what value you should be reading.

Oh! And you can also test your meter with a potentiometer. If you
don't have one most electronics stores like a Fry's will have them.
A 1/2W 0-100 Ohm Pot would do.

Thank you, clear as glass now......

muttandjeeps wrote:Thank you, clear as glass now......

Did you get your gauge working? In tackling mine next and following both threads. I can power mine and get a full sweep but when installed as outlined here I only get empty. New sending unit installed but have not ohm tested it.

Check the wire between the sender and the gauge, it may have been cut or damaged somewhere under the truck; but the most likely issue is a bad ground at the tank. I have had success putting a ring terminal under one of the sender screws, and bring that wire to a good chassis ground. This has helped some "iffy" gauges.

No real luck. Wired gauge correctly, still funky. Re wired to the sending unit, both sender and ground, still useless. I guess the next step is to RR the sending unit, but have gone to the time proven resetting of the odometer at each fill up....

Try hard wiring the "G" terminal to the Ground lug. You should get a SOLID Full reading (slightly higher than full) and 100% stable.
If you have a 40 to 50 Ohm resistor laying around then put that in series with "G" and ground, you should read a SOLID 1/2 full (bit below at 40
and a bit above at 50) -- but SOLID and stable. If not then you got something funky with your gauge or connections to it. If meter is good your
sender is the bad boy or ground or "G" signal from it. Ground there relies on chassis path, might be a bit corroded. You can also Ohm out the
sender at it's terminals (El cheapo meters at Harbor Freight).

Thank you guys for the replies and suggestions. Spent a little more time tonight after mounting a d wiring the new winch, but all I got was the fuel gauge lamp working. Progress!