Add coolant alert on 2012 ML350 BlueTec, any help?
 

My 2012 ML350 Bluetec gave 2 alerts this month to add coolant. Anybody else having this problem? Does somebody knows where usually this car leaks coolant? I just want to be prepare before talking car to service. Thanks.

The coolant warning system is quite "sensitive" - and if you have genuine MB coolant you shouldn't be too concerned - and YES, have the dealer diagnose the potential "leak".

If a non-MB/non-ph-neutral coolant has been used in your MB - that can drive the sensor a bit crazy too.

Are you in fact losing coolant and are low? ...or is it a faulty sending unit reporting low coolant for no reason. On my E550 the sending unit went bad and they had to replace the plastic coolant overflow container with the sending unit attached.

Still losing coolant
 

The car is in fact losing coolant, I had to add it a few times now.

I am using MB original coolant fluid.

Thanks

Re coolant. ALWAYS use MB product. There are many different alloys/metals in engine system. Do not use any universal (works in any system) coolant.

Any coolant on the ground under the car in the mornings? Or any other time?

I had a leak from a hose connection right at the radiator. It was half way down the drivers side on the engine side. It was real difficult to even see the fitting. It dripped onto a panel on the bottom of vehicle so it never left anything on the garage floor. I'm guessing it would blow off as soon as I started driving. Used to add 32 oz of MB 50/50 coolant mix every two months when the vehicle asked nicely. Ended up reading it in that way

Thanks to all, car is at the dealership right now, I will post results.

Yeah, sure you will .....:rolleyes:

We bought our car brand new from Benz in 2012 and have serviced it with them all this time, so it had only ever had Benz coolant. Over the last few years we have had two coolant leak issues, so here are some places you can check;
First leak came about because the new hose clip design, which attaches the hose to the radiator, had rusted and come loose. It has been designed so you must replace with a Benz hose, you cannot use a regular clamp.
Second leak this time is from the right hand top plastic mount that holds the radiator in place. Need a new radiator to fix this, I found reasonably priced OE replacements at RockAuto. Hope that helps

Mine is leaking in the exact same spot. I'll try using epoxy see if it can stop the leak. Strange place to leak.

Me too observed the coolant leak at the same spot (...leak is from the right hand top plastic mount that holds the radiator in place...) after low coolant warning and coolant liquid at garage floor.
So I took off its plastic cover and rubber insert, cleaned the area from coolant of that mount and than verified that coolant comes from the inside of that mount - I believe from tiny crack in that plastic part of radiator.
Hence decided to give a try to fix it with epoxy (J-B Weld Original Cold-Weld Steel Reinforced Epoxy) before replacing the radiator by filling the space of the mount with epoxy.
So far so good -
https://cimg9.ibsrv.net/gimg/www.mbw...963a8e486a.jpg
https://cimg0.ibsrv.net/gimg/www.mbw...78964cb6a6.jpg
no any leaks observed - see pics.

Hi Oleg, thanks for sharing. I have a coolant leak and my mechanic did a pressure test and showed that exact same spot you have your leak. He mentioned it was a weird spot that he hasn't seen leak before, but said we could try to use epoxy and see if it stops the leak. If not, I would need to replace the radiator.

How has your epoxy held up so far?

After epoxy applied as described before there is no absolutely any coolant leaks any more. Performed many long runs during last month with epoxy, checked every day for leaks and it's fine.
That epoxy has strength 5020 PSI and if applied correctly (cleaned and sanded surface, mixed right) should be no problems.

Worked like a charm! Thanks!

Mine is leaking just beside the radiator (same spot as you). Is there any video how to open and fix it?