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There is not a lot of direct EQC chatter that I can find in france but so far i have not seen any similar complaints. However a french reviewer made the specific point about how the car in semi autonomous driving uses data from the cameras and topographical data from the navigation system to control the car and as a result the braking feel was variable. I have seen similar references elsewhere. So maybe a starting point would be to see if the problem only arises in I assume D auto when the cars brain is engaged and it is that that is altering the feel of the brake because the car is already taking action to slow itself one assumes possibly by a mix of regen motor braking and traditional hydraulic braking. I also wonder if our Australian cousins have any comments particularly Natroth who I know has had his car for a year plus.
 

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I can replicate some braking issues. If you put the car in D-- mode drive relatively fast lift off the throttle so regen hits -80 and then if by chance you hit a pot hole, the brake peddle is a mess. Still havent found the culprit for the peddle going rock solid though which is my biggest concern, this seems to happen out the blue and virtually impossible to drop without then having to smash the peddle to the floor to which it skids and abs cuts in. Worrying.
 

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Hi @Henliston, does the braking change at all or is it just how the pedal feels?
Hi We have now had our EQC400 in the garage for a 4th time, car brakes failing to operate. The brake pedal doesn't, travel and is solid or rock hard, we are very concerned that we will cause a incedent, this problem as now happens 7 times, the car is 10 months old. After 4 months the care needed a new hard drive, the car doors automatically locked with the key inside the car and we now have another intermittent fault coming on the panel saying Active Brake Assist, currently limited See Owners Manual. We need help, me and my wife have been driving Mercedes since 1980 and owned around 50 cars with no issues, what as gone wrong.
 

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Sorry to hear of your trouble. I have had no issues with the brakes on my car albeit the feel of the brake pedal is more variable than previous cars I have had depending on the aids that may or may not be in use ie if I am using just dAuto, or with cruise control and the full driving assistance system or with the limiter only. The ABS does seem more sensitive and cuts in more than I have l previously experienced on my other mercedes. But I cannot say I find the difference in feel in anyway troubling and the car always feels under control.
Re the keyless go system (first car I have had with it) I was surprised it was possible to lock the car with the keys in it but it can of course be opened with the app….we do find that having two people carrying their own keys can sometimes be a source on confusion and if the car is opened by one key which goes out of range because it demands the key be put in the centre console likewise if one is plipped from afar to open the car and then the other is used to drive it. Also noted the other day when washing it with a key in my pocket the car was opening and closing seemingly randomly but actually it was the effect of wiping the car down triggering the door switches….remember to put the keys somewhere else out of range next time! Overall however the kick to open the tailgate is almost flawless and when it fails it is simply not having the relevant key the car has latched onto close enough.
I have experienced error messages on the freinage de urgence assistance (Active Brake Assist) with a sprecific warning it is temporarily unavailable (in french so I do not know the message used in the english versions). I have also experienced the same for the assistant adaptif feu plus most frequently. Both have occured on dark wet misty or very wet nights and both have cleared quickly. On looking at the manual it is clear the systems can stop working in the event of rain or wet and cold damp conditions, I think the camera lense mists up as it usually happens early on in an evening run and clears a few mins later as the car warms up a bit (as much as BEV do). I have experienced warnings re the driving assistance system before on my e class in very heavy rain. The manual states this can be the cause and the system will switch back once conditions allow so what is the specific warning you get is it referring to a temporary failure or does it say that the function is limited? According to the manual if you do not have the pack assistance de la conduite (driver assistance package) you need to take the car to a garage if you get the message.
It might be there is nothing wrong with the Active Brake assist be interested in your response re the type of message and what pack the car has.
Re the key is there any possibility of the other key being responsible?
Brakes other report similar but not sure if it is merely on the continume of the brake system feeling different, I have always assumed due to the effect of the drive train and regen hydraulic systems working together in a way none of us have experienced before, or if there is some sort of bug in the system that can on occasions seemingly lock the brakes but surely pressing on the pedal causes a physical reaction unless of course it is fly by wire. Mercedes are very safety concious and I would not expect them to take risks on brake systems but who knows? Let us know what your garage say.
I do find that the pads stick so there is often a firm clunk when I pull away after the car has stood overnight. I use dAuto all the time and brake as I normally would and the discs look clean and not rusty, my e class would do it occasionally…
When a car does not deliver as you hope it is frustrating and upsetting and even worse when people like me rock up saying they have no problems. Why did they replace the hard drive by the way?
Good luck and let us know how you get one.
 

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I have the same issue. Random non responsive breaks. I put it down to being an electric car, but this is not good enough from MB. When I hit the breaks I don't know what kind or response I am going to get.
 

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I have the same issue. Random non responsive breaks. I put it down to being an electric car, but this is not good enough from MB. When I hit the breaks I don't know what kind or response I am going to get.
So are you saying the car does not slow in anyway? What do you do to bring the car under control? Have you spoken to Mercedes and what are they saying? Or is it that the car does not respond as you expect and is not slowing as you expect it to. Is there a particular drive mode it happens in or when using a driving assistant sytem?
Am not sure one can say it is not good enough from MB poor brakes are not good enough from any manufacturer. What is hard to fathom is what is causing the issue and also to understand how the problem could arise ie is the hydraulic system controlled electronically thereby enabling it to be prevented from operating if the wrong signals are sent or received. I would have expected the system to have a failsafe position that it can at least always be operated manually.
In the manual it does make it clear that if there is a brake failure and the red warning light comes on then the brake will feel different and may need different pressure, maybe the problem is something to do with it defaulting to a non assisted system ie as when the servo failed on older systems, just thinking out aloud but it is something that needs a response form mercedes.
 

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So are you saying the car does not slow in anyway? What do you do to bring the car under control? Have you spoken to Mercedes and what are they saying? Or is it that the car does not respond as you expect and is not slowing as you expect it to. Is there a particular drive mode it happens in or when using a driving assistant sytem?
Am not sure one can say it is not good enough from MB poor brakes are not good enough from any manufacturer. What is hard to fathom is what is causing the issue and also to understand how the problem could arise ie is the hydraulic system controlled electronically thereby enabling it to be prevented from operating if the wrong signals are sent or received. I would have expected the system to have a failsafe position that it can at least always be operated manually.
In the manual it does make it clear that if there is a brake failure and the red warning light comes on then the brake will feel different and may need different pressure, maybe the problem is something to do with it defaulting to a non assisted system ie as when the servo failed on older systems, just thinking out aloud but it is something that needs a response form mercedes.
I'm not a mechanic or engineer, just a driver of 30+years. I know what good brakes should feel like. It is the feel of the brake pedal that is inconsistent. I'm not going to waste my time going to and from the dealership.
 

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I'm not a mechanic or engineer, just a driver of 30+years. I know what good brakes should feel like. It is the feel of the brake pedal that is inconsistent. I'm not going to waste my time going to and from the dealership.
Well your reply has cleared up some of the concerns, you are in effect talking in a similar way to me that the brake pedal does feel different at different times and I think that we both seem to think the same that it is due to the electric drivetrain ie electric cars which use regen as well as simple hydraulic braking feel different. That is not the same as there being some sort of failure in the system giving some users problems.
I personally have no issues with the variable brake feel but clearly some users do. What would be interesting is to see whether users or other manufacturers electric cars have similar opinions to try to see if it is a mercedes electric car issue or if electric cars in general might throw up similar experiences being discussed on this forum. I did try searching for other info on this topic and so far have not found anything but I will continue looking. Maybe we could see what EQA drivers think?
I shall have a little play with mine too and see if I can replicate the rock hard feeling on demand so to speak.
 

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I can see that I have same problem.
Only with this Mercedes, have drove quite many another Mercedes.
Agree this car is different I am on my 5th mercedes e class, GLK, c class, e class and now the EQC. From the GLK on they were all 4matic though the GLK system was different to the later c and e class but all of them were permanent 4 wheel drive whereas the EQC is an electronic system as we know and the car generally runs in FWD.
So my feeling is we are talking about potentially the specifics of this car and its interaction with the electric drive and all the other electronic drive systems it employs not a failure in systems in some specific examples. I see this as quite a big difference in the nature of the issue, ie it is not a reliability issue but a design issue.
As I have said before am interested in what drivers of other BEV think about their cars or is this a specific mercedes issue or tighter still just an EQC issue🤔
 

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I recetly bought an EQA, this EQA was a Demo with 11k Km, when the dealer wanted to deliver the car, the car didnt pass the brake test, it seems the wheels not braking at the same strenth, then the Dealer deliver me new one with 78Km, i guess maybe some problem with brake system in theese cars? Time will tell...
 

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I have a GLE350de with the exact same problem. I've been feeling the "brick under the pedal" about a dozen times in these first 12 months. Quite unsettling every time. Yesterday I was slowing down a 90km/h road to take a right turn and the break flat out didn't respond properly. I missed the exit with 30-40 meters. The weather was bad and it was snowing, maybe some sensors were covered. If I had had someone in front of me it would have been a disaster.

I feel relatively certain that it is a break regen issue. I got a shop slot in about 2 weeks, not certain I dare use the car until I get it to the shop. Sorry for the OT car model, but I just wanted to report what I have experienced. I think Mercedes has a general problem here.
 

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I have a GLE350de with the exact same problem. I've been feeling the "brick under the pedal" about a dozen time in these first 12 months. Quite unsettling every time. Yesterday I was slowing down a 90km/h road to take a right turn and the break flat out didn't respond properly. I missed the exit with 30-40 meters. The weather was bad and it was snowing, maybe some sensors were covered. If I had had someone in front of me it would have been a disaster.

I feel relatively certain that it is a break regen issue. I got a shop slot in about 2 weeks, not certain I dare use the car until I get it to the shop. Sorry for the OT car model, but I just wanted to report what I have experienced. I think Mercedes has a general problem here.
Worrying can you keep us updated. My only issue is thst the ABS seems far more sensitive than on my old e class but so far have had no brake problems.
 

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Just left the car in the shop to pick up a loaner. I found my mates GLE 350de in the lot. Called him up and he had the exact same problem braking for a roundabout. Brake didn't respond properly. He was just as scared as I went straight to the shop! The car has had some "drivers updated" and was told he could pick it up again. No error log messages found. Will keep you all posted as this develops.
 

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Just been looking at the owners manual on my car (EQC) for something else and spotted that there is a very clear message in it that the braking effect (or as they say in french in my manual limits of the system) of regen varies or is even inexistant according to certain conditions, if the battery is highly charged, if the battery has not yet reached its operating temperature,when you are close to stopping, when the car is in neutral,during and after a regulation by ESP.
It then says in these cases the braking will be regulated by the intermediate system of brakes. If necessary brake equally/also (my translation) with the help of the service brakes.
So I read that to mean that the regen braking is variable and the car brain will bring in the friction brakes but that the driver can also add to that by braking as well if the driver thinks more braking is necessary. So the suggestion the brakes feels different which many reviewers refer to is no doubt related to the regen system and how much it and the friction system are sharing the work. We the drivers may not be attuned to what is going on as it is seamlessly happening.
So looking at the issues reported here is there some sort of problem with the brain controlling the response of the brakes when activated by the break pedal? Are they even mechanical from the pedal with a hydraulic slave cylinder as in days of old or are they fly by wire? Must have a look tomorrow to see if there are any signs under the bonnet which would indicate. If it is a software issue it is a bit scary for sure but have to say never had any issue thankfully with mine.
I should point out it is in the section discussing the different settings for regen which I think is not available in hybrids but in the EQC you can pull on the righthand paddle and slow the car without touching the breaks.
 

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Hi all
I have had my EQC for a year now and it has just gone for its first service
Told the dealer about my issues with the brakes as described by others on this forum
Pothole and wet drain covers making regen cut out and hard brake pedal even if i remove foot from brake pedal and reapply the regen does not kick back in and pedal is still hard
Dropped the car off first thing in the morning and by mid afternoon i received a phone call to say my car was not very well
The technician had gone out in the car with the regen disabled and came straight back as the brakes were Dangerous ( no assistance )
They then plugged it in to reset/ reprogram what ever they needed to do
Apparently there are 7 systems to do and it completed the first 3 or so and then froze up and now i am with out a car untill they find out what is going on
There is a recall that needed to be done to it as well for a reprogram of something to do with the battery or charge control but they have not got that far yet
Also the sat nav stopped working along with the sign recognition a couple of months ago
Not what i would expect from a brand new car
Very disappointed indeed
 

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The technician had gone out in the car with the regen disabled and came straight back as the brakes were Dangerous ( no assistance )
It'll be interesting to hear the details of that failure - what gets replaced etc.

It feels like they've used a conventional vacuum booster, presumably with an electric vacuum pump to provide the vacuum. If you get in the car, leave the ignition off and operate the brake pedal, you get about 5 actuations before you run out of vacuum boost. At that stage the vacuum sound vanishes, and the pedal becomes much firmer to push - that might be the "brick under the pedal" feel that people report. If you then turn the ignition on, the vacuum is restored and the pedal feel returns to normal.
 

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Pothole and wet drain covers making regen cut out
I've sometimes noticed that behaviour. I'm almost always in D-- so when I notice it, my foot isn't usually on the brake pedal. I need to quickly find the brake pedal to take over slowing the car down. Happily though, I'm always met with an effective boosted braking experience when I do.

That experience is also pretty common when doing extreme off-roading (not in an EQC) and I suspect its root cause is roughly the same. When you're coming down a steep rutted track in your old diesel LandCruiser in low range, if you don't have any diffs locked, and you don't have any new-fangled HDC technology engaged, then when you unload a wheel (getting it in the air because of a rut/hole) you lose all engine braking and the car lurches forward thanks to gravity.

Most ICE drivers don't do off-roading, don't have low range and so have little experience of heavy engine braking. My LandCruiser in low range feels a lot like my EQC in D--, lift your right foot off fast enough and they both try to stop hard... at least until something disturbs them enough they lose traction. In the case of the EQC it doesn't take much - a pothole or slippery manhole cover as you say.

If you're driving your EQC in D and just using the brake pedal to slow down (which I imagine is what most people do) then it all becomes even less intuitive. The first part of your brake pedal travel is engaging "engine braking" and so is subject to those quirks described above.

In any case, having no vacuum boost when you eventually get to needing the real brakes is a definite malfunction, probably hidden by the fact that for the most part you were getting by fine with just regen braking. Let us know what they find.
 
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