[elau]

Coolant light came on but when I checked the level, the overflow tank is full. What gives? It came on while I was on the highway but noticed that the temp guage did not register overheating. It first came on intermittenly and now stays on all the time. It is a '96 C280 Sport. The windshield fluid tank is full as well, so it cannot be the idiot light.

What can I do to stop the light from coming on, except having the entire cooling system flushed? And will it be more sinister problems lurking around that I should be aware of? Will I hurt the car while the light is on? Any help is appreciated.

 

[J-Dogg69]

Check the aux. fan works, could be an open circuit to that fan or missing fuse...

 

[BenzMaster19]

The coolant light will not indicate an overheating engine, it will only indicate a low coolant level. My '95 C280's light came on aswell, and it looks like it will come on when the coolant level reaches just under the "HALF" way mark on the overflow tank. IF its actually full, then I would like to think the sensor has gone bad, especially if the level is fine!

 

[bmeister]

I read somewhere perhaps on here that the sensors, windshield and coolant run in tandem. Maybe I am wrong. I suspect one or both of your sensors may be faulty. I would suggest jumping one connector sensor with a paper clip or resistor to see if it goes away if it works you found one problem. There have also been posts about repairing the sensor (s) with rtv silicone, they will leak after a while and expose the element inside the sensor (s) don't know if the repair would be worth the time vs. sensor replacement. As long as you have checked your coolant cold and hot and there is fluid in the tank with no hose restrictions your probably o.k. for now despite the annoyance. BTW tell that lady to get a sports bra B

 

[liquidusculade]

well i would say that if the tank is full and the car is not overheating then it sounds like its your sensor. the windshield washer fluid is seperate and has a seperate light. make sure with your owners manual that the light is actually the low coolant level indicator.

 

[keepsitsimple]

I am experiencing this problem too. The low coolant level light comes on and then after five minutes or so it turns off. Engine temperature has not crossed over 100 degrees Celsius and the water/coolant level in the coolant reservoir is full. In an effort to diagnose the problem after having read this post I tried something... with the car running and the low coolant level light on, I tried un-plugging and plugging the windshield washer fluid level sensor connection, to my surprise the low coolant light went off. I got happy and drove off but in a few minutes it turned on again. I am gonna replace the windshield washer fluid level sensor first as advised by my indie. Will update the gang with the results.