2001 GMC Check Coolant

intermittently.

Have been waiting to see if someone more knowledgeable than me knows something about it. I will make a guess that you have a loose wire. I am not certain where that sensor is but think it is someplace on the front side of the tanks. Can't say how to get at it either except perhaps removing the headlamps.

I had a service tech friend tell me all you have to do is pop the hood and add about a glass of water to it. Sure enough it worked, but it kept coming on. Upon the 100,000 mile check up they did a coolant flush and everything like that and it hasnt come on since. 99 Silverado here