How to reset low coolant warning?

The reed switch may be stuck. My 98 Grand Am coolant tank ran dry last week when my lower intake manifold gasket started to leak. Fixed the leak and refilled the tank only to see the coolant light still on. Tapped the switch/sensor on the bottom OS the tank with a rubber mallet so the magnetic float could loosen up and float back up. Sure enough, turned on the ignition and light was out.