01 Impala coolant light

My low coolant light comes on and off at random. I checked the coolant tank for a level sensor like on my Cavalier. Surprise! No sensor. How does this car know the level?? Of course the radiator is totally full and the coolant tank is full to right mark. It runs fine and doesn't over heat either.Thanks

If you have a 3.8, your coolant level sensor is not in the recovery tank. It is on the passenger side of the radiator. They are known to get gunked up and then give false readings. Remove your battery and you will see a small gray or black square on the side of the radiator. That's it.

The previous poster is correct. The sensor gets gunked up with sludge and most of the time, removing it and cleaning it will fix the problem.

I have a 3.4 but I will look for the black box. Could it be somewhere else? Thanks