How did you test it?
As it will give a voltage out normally around the 2 volt mark, but any changes in the voltage will be in the mV range either side of the 2 volt depending how the load is applied to the cell.
Google "strain gauges" as these are what the cells have stuck to the block of metal to measure the tiny flex in the metal, it will give you a much better understanding on how a load cell works.
Normally to test a cell you would use 4 resistors configured as a wheatstone bridge with somewhere around 470 ohm resistors.
If the cell has been over stressed then it is useless attempting a repair.
If the cell is still mounted in it original location then check for corrosion or rust under the cell, as i have had many that a small amount of rust can place enough pre stress on a cell to over load it before weight is applied.
We are talking a mere fraction of flex in the cell for maximum reading, and corrosion or rust under the cell can cause this very easy.
Pete.