bha1980

Hello everyone. I drive a 2010 GLK 220 CDI 4Matic and was hoping for some advice.

It started getting cold here about 2 weeks ago and the 'top up coolant-check owner's manual' has been popping up. However, after driving for a few minutes it would go away. Around the same time, the wiper fluid light came out. I went last week to check the coolant levels; the guy checked and it was completely full and also topped up the wiper fluid.

I read somewhere that the sensors for these fluids are connected; that even though the coolant was full, the light went off because of the low wiper fluid. The message went away for a day but every morning when I start the car, the coolant message comes up again. And again, it disappears after awhile.

Is there any way to reset this message or should I take it to another shop soon? I think it's because of the colder weather. If I park my car in a warmer section of my garage, the message tends not to pop up.

My A2 service is coming up in December so I was just hoping to do everything then. I stopped taking it to Mercedes last year since they absolutely gouge you on the service here that another shop can do for a fraction.

Any advice would be much appreciated.

Thanks in advance.

Plutoe

The sensors are not connected---very bad advice!!

bha1980

Thanks, I'm going to go to the shop soon to see what the issue is.

Marek_Norway

I have the same car as you, once I got message about coolant, I had leak around fuel filter holder 2 years ago, another was this summer, I topped it with coolant and it went off (probably little amount evaporated during 2 years, becouse after this I drove more than 2000 km trip and coolant level is still ok)...every winter especially when is below 0, I get message about wiper fluid even if it is fully topped, but it depends on what brand of fluid I use...and no, these sensors are not connected...

bha1980

Thanks. It only goes off when it's cold and when the car heats up, the message disappears. When I went to check it, the guy said the coolant was full so don't think it's a leak. Regardless, will get it checked out again.

Thanks again.

bop11

What guy? Coolant expands when it is heated, so yes, you are low but only a little. Top it up when it is cold ( book says below 158°F) to the marks in the expansion tank. For cold engine, coolant at level of the top of the marking bar in the expansion tank,. For warm engine level is .6" over top of bar. Coolant should be of pre-mixed for 35°F with corrosion protection for aluminum. A more concentrated solution will cause the engine to run hotter due to poorer heat transfer.
From this you can see that the coolant level goes up more that .6" when the engine is hot and will turn off the add coolant light when it is just slightly low.

bop11

That should be -35°F

bha1980

Great, thanks for the detailed advice. I will bring this with me when I get it checked out.