1997 C180 Sport Coolant level warning won't go out.

[westcountrycars]

The coolant level is right to the top of the filler but the sensor has it's own hole in the top of the radiator. When I removed the sensor it was wet but I can't see down the hole very well. I have changed the level sensor. My mechanics have tried by-passing the sensor but the light remains on the dash. The washer bottle has it's own sensor so it's not tied with that. The fan is belt driven so it's not related to that. Incedently, when I disconnect the washer bottle level sensor, the washer low warning light doesn't come on. Same with brake fluid level sensor. Can anybody explain how these sensors work and how I might be able to get my coolant warning light to go out.

 

[Iain the gadget]

Have you taken the feed off the sensor and shorted it out?

 

[bigasotonuk]

Hi,
This went on mine exactly same scenario, i replaced the "washer" fluid level switch this fixed the problem, they share the same wiring somewhere.
MB Parts man told me, i thought "wot a tw*t" don,t know wot hes talking about as i walked out of dealer, i was back 3 hours later he had one the counter ready for me as he said i knew you would be back.
Very surprised exactly how cheap both these switches were.

 

[westcountrycars]

Yes, our mechanics tried shorting it but the light remained on. Do you think they may have done some damage? Thanks for your interest.

 

[bigasotonuk]

Hi,
I personally don,t think any damage would of been done by shorting it out but really as crazy as it seems the problem is with your washer fluid level switch this i,m 110% sure of

 

[westcountrycars]

Thanks andy, I'll try changing the washer level sensor and let you know.

 

[BRUCE LEARMONTH]

Thanks andy, I'll try changing the washer level sensor and let you know.

apparently washer sensor and radiator sensor goes hand in had for some reason replace both so i am told

 

[bigasotonuk]

Hi,
no need to replace both i only replaced the washer switch when my coolant light was on.

 

[westcountrycars]

I changed both.

Hi guys, Thanks for your advice. We ended up changing both but it wasn't that easy because we ordered a non-genuine radiator sensor which didn't work. It had a bi-metalic switch in it which we had to by-pass maybe it was designed for a different model, one with an electric fan or something. It's sorted now. Thanks very much.