Howdy,

I have ordered an E55 for Jan delivery and I have picked up that there have been significant issues with the brakes on the S class in particular - and in some cases with the E too.

What is the current situation at MB and what is being done to resolve the problem? I recently heard of a case back home where an S class had full brake failure (around 13000 km on the clock). They replaced the car with a new one - while this is perhaps the least they can do - I understand they have replaced around 20 units in South Africa alone because of this issue. Not sure if they are all S classes though.

Apparently there is also a class action suit pending in the US on the same issue. Just google 'Mercedes benz brake failure' and you will find it.

I am very concerned about this ... but am also very interested to know what MB is doing to fix the problem beyond exchanging cars.

Jeepers what has happened to MB ? They were the epitome of German engineering and quality ... certainly cannot say that now.

Rgds Steve.

 

Steve,

I'm sure if you do a search for "brake failure" you'll get more info than you really want. I had a couple threads on this issue about a month ago when that failure happened in my '03 E55. The long and short of the problem is a malfunctioning SBC (brake control) unit. When this happens you lose all braking ability. The ECU takes over and downshifts the car (safely) to 1st gear. Very frightening and potentially dangerous. However, the notification on the dash is unmistakable and as long as I knew what was happening, I was able to react to it. Ultimately, I took the car to a dealer where they replaced the SBC under warranty in one day. I do not know what measures have been taken to correct the problem, but I would not let that stop me from buying this incredible vehicle.

 

That is the ONE issue that is keeping me from buying an E55. I like everything else about it...everything. However, brakes are VERY important, dont cha think?

I could hardly believe that you would say not to let the fact that you may have total brake failure yo keep me (or whoever) from buying an E55. lol. That blew my mind. To me, it is a huge issue. At least hydrualic systems are somewhat redundant (can still brake two wheels if one line leaks)...with a SBC failure, you have NOTHING. That is fricken insane.

I still dont know what to do. I really like the E55 but dont know if I would ever feel confident with the brakes. The SBC would always be in the back of my mind as I strap my 3 year old in the car. i dont know if I could live with that.

I am still on the fence with my buying decision, but I have to make a change quickly. Realistically, the only two "comparable" cars (IMHO...price, power, etc.) are the M5 and the Audi RS6. I am leaning RS6 right now but have yet to drive one.

I am somewhat torn up inside about this. The E55 is the car I want. I just dont know if I could live with knowing the SBC could fail and leave me ripping towards a parked semi...with only engine braking. It could be really ugly.

 

I have sent the MB guys here a mail reagrding this issue. I want to know what they are doing about it besides giving people new cars.

I will let you know what i get back.

I understand that the system has got a hydraulic back-up from what I have read on the forum - i.e. if you push / pump pedal all the way to the floor board this secondary system becomes active ... if this is the case I am a little less worried - but it would be great if someone can confirm this.

Rgds Steve.

 

Roger that. That would be a big relief to me as well. However, one guy said he basically had nothing....just the engine downshifting to slow the car. I wonder what the real deal is. Please post what you find out. I will do the same. Tim

 

I think a lot of the brake failures are due in part to improper servicing of SBC, owners not getting the SBC system updated. I have never had an SBC failure, nor any error message of sort in the 20K miles I have on the E55.

The E55 and every SBC equipped car does have a hydraulic backup system, but you have to push fairly hard on the pedal.

 

2005 Mercedes-Benz E-Class E320 NHTSA Recall ID Number: 05V133000
Recall Date: APR 01, 2005
Component: SERVICE BRAKES, HYDRAULIC
Potential Units Affected: 204000
Summary: ON CERTAIN VEHICLES, THE SENSOTRONIC BRAKE CONTROL (SBC) SYSTEM MAY PREMATURELY SHIFT TO THE HYDRAULIC BACK-UP FUNCTION MODE, DUE TO DETERIORATION OF THE WIRING HARNESS CONNECTION, OR DUE TO PREMATURE FAILURE OF THE HYDRAULIC PUMP.
Consequence: IN THE HYDRAULIC BACK-UP MODE, THE DRIVER HAS BRAKING POWER SUFFICIENT TO STOP THE VEHICLE, ALTHOUGH GREATER BRAKE PEDAL PRESSURE IS REQUIRED AND THE BRAKE PEDAL TRAVEL WILL BE NOTICEABLY LONGER.
Remedy: DEALERS WILL INSTALL A BRACKET AND REPLACEMENT GROUND WIRE TO THE SBC PUMP UNIT ON ALL VEHICLES. ADDITIONALLY DEALERS WILL INSPECT AND REPLACE THE SBC PUMP UNIT IN SL VEHICLES PRODUCED DURING A LIMITED PRODUCTION PERIOD. THE RECALL BEGAN ON AUGUST 8, 2005. OWNERS MAY CONTACT MERCEDES-BENZ AT 1-800-367-6372.
Notes: MERCEDES-BENZ USA, LLC., 2005070007
2005 Mercedes-Benz E-Class E320 NHTSA Recall ID Number: 04V296000

Recall Date: JUN 22, 2004
Component: SERVICE BRAKES, HYDRAULIC
Potential Units Affected: 143387
Summary: ON CERTAIN VEHICLES, THE ELECTRONIC MONITORING SYSTEM OF THE SENSOTRONIC BRAKE CONTROL (SBC) IS DESIGNED TO MONITOR THE PRESSURE GRADIENT WITHIN THE HIGH PRESSURE LINE OF THE BRAKE SYSTEM. IF AN UNACCEPTABLE PRESSURE GRADIENT IS DETECTED, THE SYSTEM WILL SWITCH, AS IT IS DESIGNED TO DO, INTO THE HYDRAULIC FUNCTION MODE.
Consequence: IF VEHICLES ARE NOT ROUTINELY SERVICED AND HAVE EXTREMELY HIGH MILEAGE COMBINED WITH A HIGH NUMBER OF BRAKE ACTUATIONS, OR A HIGH BRAKE ACTUATION FREQUENCY, THE PUMP MOTOR OF THE SBC MAY RUN OUT OF PERMISSIBLE TOLERANCES, THEREBY TRIGGERING THE HYDRAULIC FUNCTION MODE.
Remedy: DEALERS WILL INSPECT THE SBC HYDRAULIC UNIT, REPLACING IT IF NECESSARY. THE RECALL BEGAN ON OCTOBER 21M 2004. OWNERS SHOULD CONTACT MERCEDES-BENZ AT 1-800-367-6372.
Notes: MERCEDES-BENZ USA, LLC., 2004050014

 

I can confirm that when there was brake failure, with increased travel and effort, there was stopping action. I found engine braking to be more effective. Let me also clarify that I'm not strapping a three year old in the car either. That might give me a whole new perspective. We all take our lives into our own hands every day getting into ANY car. My only point was that if I am aware that this could possibly happen and I know how to react, unless it happens at just that right time when I can't react (out of my control), I'm OK. Personal preference. No different than climbing into your SUV knowing that if you have to aggressively swerve to avoid some moron (out of your control) you may end up on your roof!

I was just putting my $.02 regarding whether or not this would stop me from buying the car.

I would still like to know if the supplier has diagnosed the issues, changed the unit, or solved the problem. So if anyone hears anything, please keep us "posted".

 

Thanks for all of that good info fellas!! At least there is a hydro back up, etc. That makes me feel much better about it!

AMGcrazy - I meant no disrespect. We all have our own concerns, etc. From what I read previously, it sounded like you would basically have no brakes at all with an SBC failure. It is very reassuring to know that there is a backup (as I was hoping) in case of a failure. I can't imagine them NOT doing that, and was hoping they did. Good to hear it is there, just in case.

See, I am a former "track nut". I have tracked for many years and instructed for a while too. One thing I love is late braking on people....a race can be won on the brakes. So, when I heard about brake failures on the E55's, I was like "wtf...screw that". Brakes are important to me in more ways than one I guess... Now a'days, I dont have time to track at all.....maybe a few times a year if I really tried, but I am a bit burnt out on it anyways. I am going to sell my GT3 and buy an E55 or RS6. I was leaning RS6 onoly because of the SBC issue. Now that I know there is a backup etc, I am leaning E55 again. I like everything else about the car.....

thanks again for the info. I apprecaite it. Tim

 

Mmm RS6 perhaps only makes sense if you want the wagon and 4wd which is quite handy.

E55 has got the nuts of a motor ... awesome. Thats the deciding factor for me...

Rgds Steve.

 

yeah, there is always hydraulic brakes. Merc is absolutely crazy about safety and it shows. also, it is extremely unlikely for SBC to stop functioning.

the reports of S-class with brake failure are likely due to tampering more than anything else. for one, they have a completely different braking system - it is BAS instead of SBC.

i've never heard of even one person, whom i personally know, who has ever had his SBC brakes fail on him. not saying it couldn't have happened, but it cannot be common.

AMGCrazy: no disrespect meant, but you seem to have two different scenarios of what happened when your brakes failed?

 

I guess I should have said "lose all EFFECTIVE braking ability". When the brakes went the first time, I was rolling at about 10 MPH. When my foot went to the floor and very little happened it was as if all braking ability was lost. Trust me, you would not be able to stop the car on what you have hydraulically. The only fix was to put the car in neutral and restart the ignition. Brakes would return to normal on restart. There was no rhyme or reason as to when they went out. As the frequency increased, I knew I had a problem.

Thanks for the respectful responses!

 

They answer as follows ...

"Apologies for the delay in getting back to you, I have been awaiting for
the technical department at head office to answer the below. We have been
informed that there was a recall on a number of E and S Class saloons
which may have been affected with respect to the Sensotronic Brake Control
system, it however was not a brake failure and vehicles were recalled as a
safety precauyion, modifications have now been made as a result of this at
the factory."

This is the biggest crock of **** I have ever heard ... they wont even admit there were failures ... So now that I have this in print and god forbid my car has a problem - I am going to sue the pants off them.

Edit: I have asked them to confirm in writing this has been resolved. I will now see what happens.

Rgds Steve.

 

Three days ago I had a total brake failure in my '04 SL55. I was pulling out of a parking garage, and as I braked to check traffic before pulling into the street, the brake pedal went all the way to the floor and the car rolled right out into a travel lane. Thank God the traffic light just up the street had oncoming traffic stopped.

Loud buzzers went off in the car, a "stop sign" icon lit up in the left binnacle and a "Stop Car Immediately" light lit up in the right binnacle. I crept the car over to the side of the street, and even from 2-3 mph it would barely brake to a stop.

After turning the car on and off four times, the system finally reset and I was able to drive it -- slowly -- to the nearest M-B service center, where they're still working on it.

On Day 2, the service tech told me the hydraulic pump had failed. When I asked him why a failed pump could be "fixed" by rebooting the computer, he said it was actually a computer control module on the pump that failed.

I purchased an SL55 because I like to drive fast. I'm now terrified of the M-B brake-by-wire system, since it either does not have a back-up mechanical braking system, or the back-up system fails along with the main system in certain failure modes. I cannot get out of my mind the prospect of a similar failure when I'm driving at speed.

Either Mercedes is going to buy this car back from me, or I'll be spending some time with my lawyer.

 

and that is what scares me....it appears it is only a very small percentage of cars that have this problem....however, it only takes one failure to kill me, my kid, etc. I am a fast driver too, that is why I would want a 469hp car! I am going to just stick with my GT3 for a while and wait it out...I am still a bit freaked out about the whole SBC issue.

 

Mmmmm well MB did not send me their letter in writing. There apparently is a class action suit against them being filed on exactly this issue.

For my info did you try pump the pedal or just push it to the deck ... ? Also had the recall updates been done to your car ?

I have to say when they first announced this system I thought WTF are you guys doing .... and here we have it. They need to get rid of it - but can you imagine the cost of this recall .....

Someone going to get seriously injured here and MB is going to be toast.

I have heard too many first hand stories about this.

Back to MB HQ for me - I want an assurance in writing before I take delivery of my E55.

Rgds Steve.

 

Cars do not need to be replaced but with the laws some locations have there is no other simple remedy. Mercedes is more than capable of finding the solutions people want but there are some strange and unusual exceptions.

There are some cars which simply dont make any sense. So when you consider that there are over 500,000 W220 S-Class made then 20 or so is hardly Rome burning.

There are in fact more posts and websites dedicated to the downfall of Mercedes than there are bad cars made. So when is the last time someone who was totally happy started a website. They are probably too busy driving as much as they can.

SBC has been problematic and the number of minor software updates to this cutting edge braking system has been interesting. Some dealers dont maintain their diagnostic systems and that being the case they can ruin the SBC (and thus a large part of the car) by flashing the control units with the wrong software.

Who knows why these things happen .... there are so many ways it can be the fault of the dealer or the factory.

 

If this was engine ECU - I would say fabulous ... go and play and tweak it ... but on an electronic braking system not to have a solid back up is just plain stupid.

I am far from a benz basher (i have ordered one) but geez they are not the quality and reliable product they were back in the 20th century - but they were also pretty boring then.... anyhow...

If this happens with one car its 1 too many - to say its only happened on a few cars, so its not serious, is well ... nuts.

Rgds Steve.

 

I never received a recall notice about my car (and have the same address and phone numbers as when I bought the car) and was not aware of any issues with the brake-by-wire system until the failure in my car caused me to check the internet. That was the first I heard about any recall.

My car went to the dealer at 8:00 a.m. this past Monday after the brake failure. They told me it would be ready Tuesday. Today is Friday, and they're still working on it.

The latest word yesterday was that a new hydraulic pump was installed, but when the technician went through the programming procedures Mercedes gave him for the new software, the new pump got fried by the software update. So now they're waiting for yet another hydraulic pump to be shipped.

I got into quite an argument with the service technician yesterday. He assured me the braking system simply lost its power assist and that I still had manual braking. I tried to explain to him that I grew up learning to drive on unassisted brakes, including my father's 1954 International pick-up. I weigh 230 pounds and work out regularly and am perfectly capable of pressing a pedal hard enough to stop a car without power brake assist. And I know the difference between no braking and braking requiring higher pedal pressure.

As I edged the car over to the side of the street at just 2-3 mph, I literally stood on the brake pedal. The car barely stopped before rolling into another car parked along the curb. If this is Mercedes' idea of full braking power absent only power assist, they're out of their minds.

The technician said he had called Mercedes' district service manager about the issue and was assured Mercedes had never had a total failure of this system "in the U.S." (whatever that qualifier signifies.) I told him I did not appreciate being told what happened by someone who was not in the the car when it happened. The technician said the service manager would call me back to discuss. I've not heard a word from him as of yet.

I also sent an e-mail to Mercedes' customer service line. No response from there, either.

I have absolutely loved this car up to now. There is simply nothing like it on the road (a hardtop convertible with that kind of power). But now I'm as afraid of it as can be . . . and am not getting any less so as they continue to regale me with stories of the new "corrected" software frying mechanical components in the braking system.

THIS SYSTEM IS DANGEROUS, AND MERCEDES IS GOING TO PAY A FORTUNE WHEN SOMEONE GETS KILLED. The people who drive $130,000 cars (or their heirs) can generally afford good lawyers and take care of their legal interests.

 

hmp10 - please keep us up to date on developments...

Rgds Steve.

 

This is scary stuff. I routinely hit high triple digit speeds and this is not a pleasant thought. I dropped my car off yesterday for service and some other issues (rotors that don't last a lick for one thing) and mentioned SBC to my SA. He just rolled his eyes and shook his head. IF there is a problem, I'm sure MB knows about it, but they're not gonna say. What can they do about it? You can't retrofit a traditional brake system into these cars, right? How many cars are out there with SBC. I'm sure they've already calculated the cost of a law suit to due a fatality vs. replacing / recalling / retrofitting all these cars.

 

You're freaking me out

 

Well, I got my car back Friday after 5 days in the shop with the brake problem. The service rep would give me nothing more than an upbeat assessment: "The service tech took it out and drove it a long time. Everything's A-OK." Etc.

He never would acknowledge there have been similar issues with other cars, nor, despite my request, has anyone reconciled two seemingly contradictory assertions -- that the car still had full braking capacity except for the power assist, and that the hydraulic pump had failed.

It's now been almost a week since I e-mail Mercedes' customer service site with questions, and they maintain their radio silence.

I'm in a real quandry. I love powerful cars and drive them year-round in a northern clime and, therefore, really like the hardtop convertible. I don't know with what I could replace this car in the same class . . . but it now scares the bejeezus out of me.

 

There is NO excuse for this type of failure..don't be an apologist for MB when no excuse is valid for this type of potentially fatal failure. Yeah, the tell tale lights on the dash light up and tell you...what are you gonna do when you loan the car to your mom or dad and it happens to them? Gimme a brake (no pun intended)

 

What a nightmare..can't say I blame you in the least!!! Keep us posted. That's some scary, scary **** and I'm sure MB wants to keep that under wraps at all costs!