Toby,
explain "not working". Is the gage reading empty, full, or somewhere in between?
The sender is a variable resistance, a rheostat if you will. The resistance at empty is 200 ohms, the resistance at full is zero ohms (a short circuit). The circuit is powered by fuse #12, which also powers the oil pressure & coolant temp circuits.
If all 3 gages are non functional, check the fuse.
If the gage is reading empty, this would indicate an open circuit, a wire is not connected. If the gage is reading full, this would indicate a short circuit, possible to the chassis, or between the two wires.
good luck, George
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