Gas Gauge not working

Had a problem like that 15 years ago except it was on empty. The RV dealer ran the gas down too low and the combination fuel sender and gas pump burned out. Research indicated that that was a common problem if the gas level got too low. It seems that the gas flowing through the unit also cools it. Poor design if you ask me. Had to replace the unit. Involved removing the leveling jacks cross beam, emptying and lowering the gas tank. The cost about $1,100 to $1,200 dollars. The idiots did not replace the rubber gas line connecting the unit to the metal gas line for the generator. About 3 to 4 inches of rubber gas hose. 2 years latter the rubber gas hose cracked and I had to redo the entire process to replace the hose. Luckily the second job was done by some friends so it just cost me a couple of six packs. My recollection is the tech said it could only be a bag gauge on the dash or sending unit in the gas tank. Hope it works out ok.