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Coolant warning

19281 Views 63 Replies 22 Participants Last post by  Rhys
I have a warning to add coolant, refer to owners manual. In there it says take it to a dealer. Surely this is something I can do myself? Is it just water or is there something special required?
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I would take it to the dealer as if you are having to add it there may be a leak somewhere.I have never had to add coolant to my ice cars in over 13yrs of driving various mercedes. Looking at the on line manual it says you can check the level and top up with the approriate water anti freeze mix but advises getting the car checked if the level is below a certain amount.
You can add just normal water. Sometimes new Mercedes want more oil or coolant during the first year.

Check from owners manual where is maxium level for coolant (in coolant tank) and add water. If it takes more than 5-6 dl so maybe it leaks. You will see it if car wants more coolant after adding it (for example during next month).
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You can add just normal water. Sometimes new Mercedes want more oil or coolant during the first year.

Check from owners manual where is maxium level for coolant (in coolant tank) and add water. If it takes more than 5-6 dl so maybe it leaks. You will see it if car wants more coolant after adding it (for example during next month).
Thank you.
I have a warning to add coolant, refer to owners manual. In there it says take it to a dealer. Surely this is something I can do myself? Is it just water or is there something special required?
Hello, have you solved this problem? If so, how?
Hello, have you solved this problem? If so, how?
I did take it to the dealers and they said they would have to check it and could not let me take it away. I waited about an hour and they returned it. Apparently they had topped up some coolant. Since then, it has been fine and that was nearly 10,000 miles ago
I did take it to the dealers and they said they would have to check it and could not let me take it away. I waited about an hour and they returned it. Apparently they had topped up some coolant. Since then, it has been fine and that was nearly 10,000 miles ago
They probably topped it up bit also did a quick visual to see if there was an obvious leak.
I have a warning to add coolant, refer to owners manual. In there it says take it to a dealer. Surely this is something I can do myself? Is it just water or is there something special required?
You better let your dealer check more carful ly again. I have a EQC400 myself, and have a add coolant warning three times within one and half year after I buy it. Because the coolant warning, I have change the electric machinery three times, one front twice back. many EQC owner in my region have this problem,"add coolant warning", it's because coolant leakage, some of them have cause short circuit and become serious issue.
should let your dealer open the cover plate of electric machinery, and will find coolant leakage everywhere....Hope you are not the same problem....
Doing some research the serious coolant leakage problem did not affect european cars. I have interpreted the information to mean EQC built in China for the Chinese market and the problem maybe related to either a component failure due to poor QC or poor QC on build of the car. Ihave seen no reports of this issue in europe.
First post - Recieved my EQC a couple weeks back. So far 470 miles...

This morning I recieved three warnings.
1) Battery warning
2) No tow
3) Low coolant

Could they be related?
Which battery the high tension or the 12v? Did you look at the coolant level to see where it was at?
Which battery the high tension or the 12v? Did you look at the coolant level to see where it was at?
Drive system battery - Tells me not to drive the vehicle but Merc UK could only book me in tomorrow and told me to keep driving the car.

Is what it is. Hopefully not related to the chinese recall
Drive system battery - Tells me not to drive the vehicle but Merc UK could only book me in tomorrow and told me to keep driving the car.

Is what it is. Hopefully not related to the chinese recall
Do update us and commiserations. Had my car a year now and it is overdue it’s service due to a delay in the garage having an appt to do it. It goes in next week. But there have been no problems for me but I feel for those who do have issues, these cars are by no means cheap and we are entitled to expect trouble free motoring.
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Do update us and commiserations. Had my car a year now and it is overdue it’s service due to a delay in the garage having an appt to do it. It goes in next week. But there have been no problems for me but I feel for those who do have issues, these cars are by no means cheap and we are entitled to expect trouble free motoring.
100% agree! I am hopeful it is just an airlock in the system which is the reason for the low coolant. It's low, not excessively but visibly and enough to throw the sensor.
I am from China and my wife is a EQA owner, some owner hit coolant leakage problem in our EQA/EQB wechat groups. The electrical motors manufacture by ZF and Beijing Benz declare it was import. I am wonder why only China market hit this critical coolant leakage problem? I think there should be different electrical motors between China and other countries, also Benz not tell China consumer the truth and the sadness was not one support China consumer to get the truth.

Btw, other 8 recalls relate EQC and China was excluded.

Poor Chinese
Do update us and commiserations. Had my car a year now and it is overdue it’s service due to a delay in the garage having an appt to do it. It goes in next week. But there have been no problems for me but I feel for those who do have issues, these cars are by no means cheap and we are entitled to expect trouble free motoring.
So - I finally got around to popping into a Mercedes Dealership. I'm bang between Chichester and Brighton so it's a little annoying as I tend to travel North, not east or west most of the time.

Anyway - Popped into the Chichester dealership who gave me a bottle of their finest, on the house. Got home, let the car cool down and opened the coolant tank to top it up - low and behold the level rose on its own and since has been no more warning. Air lock confirmed?

In any case, I have a spare bottle of coolant should it ever need it.

On a side note - try as I might, I couldn't for the life of me locate a Min and/or Max level indicator on the reservoir.
So - I finally got around to popping into a Mercedes Dealership. I'm bang between Chichester and Brighton so it's a little annoying as I tend to travel North, not east or west most of the time.

Anyway - Popped into the Chichester dealership who gave me a bottle of their finest, on the house. Got home, let the car cool down and opened the coolant tank to top it up - low and behold the level rose on its own and since has been no more warning. Air lock confirmed?

In any case, I have a spare bottle of coolant should it ever need it.

On a side note - try as I might, I couldn't for the life of me locate a Min and/or Max level indicator on the reservoir.
I had several coolant low messages recently on my EQB 300. Once when slowing down fast on a downhill slip road, and several times when moving off my sloped drive. I went to the dealership and they checked it into their workshop for 45 minutes, and when they took the cap off the reservoir they said it was fine and to the correct level and did not need to top it up. This was several weeks ago. It has not happened since.
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I have had my new EQC a few weeks and only have 500 miles on the clock. I had a single “battery malfunction / do not tow” on unlocking the car a couple of weeks in which reset after locking and unlocking the car. 5 days ago I had a low coolant warning. 3 days ago I had the car checked at my local MB dealer: no coolant leak or need for top up, and no record of the previous battery malfunction alarm.

The dealer did comment that they had seen this with a few EVs and it was thought to be either airlocks in the coolant or inadequate pressurisation of the coolant from the factory. No problems over the last 3 days.
Interesting - I was one that had the battery warning and Merc recovered the car. They did some software updates apparently and it hasnt come back since.

That said, they are repairing the front bumper after their tech gave it road rash in under 20 miles.
After the dealer trip mine has been fine despite having to cope with a weekend 300 mile round trip.
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