Can't get Gas Gage to work

Thinking of buying a 1998 Chevy Blazer. Everything looks good, except, the gas gage doesn't work. Seller put a new sensor in, but it did not work. Is this is easy fix and what might it be? Thanks

Thinking of buying a 1998 Chevy Blazer. Everything looks good, except, the gas gage doesn't work. Seller put a new sensor in, but it did not work. Is this is easy fix and what might it be? Thanks

We can not say without proper testing.

On testing fuel gauges always check all fuses and wiring and grounds.

Find fuel sending wire to fuel tank unit and with key on touch a old style bulb test light to it and see if light lights dime and if fuel gauge moves.

Let us know how that goes for more help.