I have a 98 Cav. that the other day the serp. belt brook. Had it replaced, and they also replaced an O ring of some sort. Anyway, my engine coolant light has been on for two days. Called my garage they told me to put some extra coolant in the reserve. I did so, light still on. Is it possible to overfill these things? What would cause the light to stay on. The car is not overheating in any way shape or form. Replaced the water pump 2 years ago. Not seeing any coolant leaks anywhere. Thanks guys...

 

I had a similar problem and it turned out to be water pump. Most shops will do a compression test in the area of $30 or so, to determine a leak, and if you had a warrantee on the water pump you did before, you may be able to negotiate a free test or diagnostic.

 

If the overflow jug is full of coolant, then it's possible that the sensor in the cooling system is sticking. I would try locating the sensor and tap on it a few times, and see if the light goes out. If the jug doesn't have any coolant in it, and the light is on, then you have a coolant leak.