96 Grans Am Coolant light ?

My wifes GA coolant light stays on.The coolant level is right up to where it should be. Just had a head gasket changed and the radiator is new,plus the therosat is new also. Anyone have any ideas why the light is still on? Thanks inadvance. 1996 Grand Am with the 2.4.

Tom

Try tapping the side of the overflow bottle were the sensor is, with the handle of a screwdriver.

They have a little float that sometimes sticks.

Thanks I`ll try that in the morning.

Tom