Coolant level low

I get this message when I first drive the jeep. A few hours later it did not come on. After 8 hours when I started it, it was flashing again low coolant level, after I drove about 20 min and turned the jeep off I started it up again and it was fine. The reserve bottle is very low but when I bought it there was nothing in it and it did not happen. Is this the problem or is a sensor going bad? Any input,thanks.

I feel your pain..........I had this happen with my 94 GC. The problem was the float in the res bottle got struck and would register low. Take the bottle out and use little soap and hot water to desolve the crud while shaking. You'll hear the float jar loose, rinse well and re-install. I hope this helps.

Well last night I filled the reserve bottle to the full mark and no more low coolant level. Maybe the float was stuck but when I bought the jeep the bottle was totally empty and no warning light at all. Anyway all's fine now. :biggrin:

General Info: the Reservoir tank shouldn't be filled to the top when the engine is cold, it should be on the ADD mark, sounds crazy but true. well the reason the lite would go out when u drive it is b/c the hot Collant would expand abd and therefore over flow into the reservoir tank, and when it cools down coolant shrinks and goes back into the system. if u fill it up to the FULL mark when the engine is cold, then when it heats up it may flow over the Tank and pour out of the top. or blow the cap off b/c no room for expansion.