Yesterday my low coolant light came on and off a couple of times. The engine temp gauge is running below the mid point as it normally does. I checked the overflow tank and noticed it was half full. My question is there is no indicator line on the tank that tells me how high the level should be. Does that mean that I should top off the tank? Any help will be greatly appreciated

 

I had the same issue. It started sporadically and after a year just stayed on. You may need to replace the Coolant Level Sensor.

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There is a rib inside that stands vertically at the rear of the tank, the correct level is when the fluid reaches the top of the rib. Basically it's to the top of the clearer part of the tank, just where the black part starts.

 

Thank you very much for the info. John