low coolant light and sensor

my low coolant light came on on the dashboard. i installed a new radiator less than 2 years ago and thought i installed a new sensor then - was told the new GM radiator comes with a new sensor already installed. should i take the old one out, clean it off, and reinstall it or just cut to the chase and install a new one? my chevy dealer has the new part for $23.

The sensor is in the overflow tank not the radiator. Might need to clean out the overflow. The sensor can stick sometimes.

//2000CAYukon

thanks for the info. i have ordered the new sensor and will just replace it. it seems to make the most sense to me seeing the sensor isn't an expensive item. the fluid is still nice and clean and is up to the full mark so i know that is not the problem or issue.

can also be just the wiring to the sensor... u checked that circuit for continuity?