kajtek1

Tell me how 600,000 brake pedal pushes is not customer fault?

mishar

You obviously do not have any knowledge or experience with this. Why don't you jump to some LED tread?

cmriv

So it's the Manufactures fault that you purchased a sbc equipped vehicle? no, it isn't. Don't get it twisted. there are units out there that are original and still working just fine.

Heatwave

And all other car makers should forever replace failed master cylinders at no cost ... n'est ce pas?

kajtek1

Hate to repeat stupid slogans, but that comes here to mind
"don't feed the troll"

mishar

No. It is my fault that I purchased vehicle equipped with brakes that would fail without warning. Manufacturers fault is that they installed such system. Units working just fine are time bombs. Just pray that yours fail at low speed.

mishar

You really do not understand the difference. Failing master cylinder start leaking fluid and sucking air in the system and brakes fail gradually. With this thing you have perfect braking and next moment red warning, loud beep and almost no brakes at all.

cmriv

Don't be upset with me. I purchased a 211 not equipped with sbc so no worries there on them failing. However once again, i'll say it, until someones seriously hurt, injured severely or killed, sbc owners are swimming upstream. Sad but true.

on that note though, in march 2005 a total of 1.3 million vehicles were recalled. so 12 years later consumers are still upset? This is a well documented issue and has been. old news


Manufactures are always trying new things. In theory a electro-hydraulic braking system is genius. Of course it is flawed, terribly flawed at that, but mercedes is the only one to introduce such things. I think toyota had something kinda similar but not quite the same. Again, you chose mercedes.... It didn't choose you. Can't blame them for being innovative/trying new things.

cmriv

red warning and loud beep have warned good enough for this long with no lives lost...... just saying. But i completely understand your point. You are still breathing which is the most important thing. And whether it gradually fails or fails instantly it's still a wear and tear component at the end of the day. It's serviceable and requires just that....

mishar

Absolutely not. But I can blame them for that lousy backup when system fails. After seven years of development all those "brilliant" engineers came with 20% braking on rear wheels when something goes wrong in that complicated mechanism.

mishar

Are you sure about that?

danielgetsthis

As someone who has experienced the fail in a very dangerous situation with no prior warning or service indicators, I agree with Mishar.

Once you restart the car, everything is back to normal and no codes are stored. One can't assume that no lives have been lost. There's simply no way for a dead person to report it and no forensic trail for an inspector to follow.

Also, I have no confidence that a service of the SBC will completely fix the "no prior warning failure". I'm fine with the line of argument that this is a serviceable item, but how is the owner supposed to know that it's serviceable if there is no indication that the service is needed? I shouldn't have to be a curious Merc enthusiast checking out internet forums.

kajtek1

Looks like we come to the point of no return.
All the topics, hundreds of replies, pictures, WIS and it can't pass simple message

cmriv

ACTUALLY if any of you would actually take your sbc equipped vehicles to the dealership or shop with das/xentry for service you would know exactly the condition of your sbc pump. It precisely tells you whether threshold is okay, needs update or is exceeded aka replace. So again, there are plenty of warnings, whether you come in for a service or request a status update. It's the consumer who is trying to save a penny, absolutely nothing wrong with that, that isn't servicing the unit or is expecting it to just do everything itself.


with all of that said, if you have a sbc vehicle fork out some money (1HR) diag fee and have them check that status on your pump.





so we can throw the gradually failing master cylinder/brake booster back in the pot because this is exactly what replaces a brake booster, sbc pump which is a mechanical part and does require attention just like other parts.

And if you or anyone took your car to a dealership or shop with das/xentry you could know every month if you wanted too about sbc. Per usual though it's always the product fault.


and if someone died from sbc you would be darn sure whomever the relatives are, are going to try and figure out what happened to a T, so miss me with that bogus nonsense....

cmriv

service threshold tells you where you are at as far as life expectancy goes for an sbc pump. Precise numbers on punches and other data all inform consumer of life left. But i suppose a unit that was designed in the late 90's is suppose to give you detailed descriptions via Ethernet cables and dial up.

writing is on the wall with this topic...... has been for a decade almost now....

mishar

No you would not know anything. After the red warning it only says "hydraulic fault". Count is way below the threshold, as it was before the brake failure. So what indicator you expect to tell you that you are about to die?

Only problem is that there is nothing gradual with SBC. It just dies when you touch the brake.

Sure. DB would volunteer detailed readout of all systems at the moment of crash. Man, hundred people die in an air crash, they find black boxes and you still may not ever know what happened.

mishar

No, no Ethernet. Just a decent backup or timely warning.

kajtek1

While in accident some things will always be left to guessing, or highest probability, technology is giving us amazing tools.
Take for example crash of Concorde years ago, who ended in ball of fire hitting a hotel.
Took investigators over a year, but they trace the issue to piece of metal trim that was dropped on runaway by other plane, that triggered chain of events on Concorde using the same runway some time later.
For those that wonder - practice SBC failure. Go on big and empty parking lot, pull the plug on the pump and do few maneuvers.
As I mention I could control 7-tons motorhome without power assistance, some W211 owners report they could drive the car with SBC backup for some distance.
Mishar is one of those who says he couldn't.
So why argue who is wrong and who is right? DO THE TEST.
Practicing emergency maneuvers is a requirement on some jobs BTW

mishar

That's actually good idea. You should be first to try, so your discussion will be based at least on that "laboratory" experience. Then you will not come back with that incomparable motor home episode.

Sure. If driving in the first gear, limited rpm and almost no brakes counts.

danielgetsthis

There are a bunch of assumptions here. I'm a new owner. I bought my w211 less than a year ago. The PO took the car to the dealer religiously since it left the lot in 2004. 82 service records to be exact. I have them all. No mention of SBC. Once I took ownership, I took it to another MB dealer to get an overall diagnostic. No mention of SBC. No service warnings in the 10 months I've owned it. My SBC failure was without warning and I blew threw a red light going 70mph. I only learned about SBC after an internet search after my deadly SBC incident.

kajtek1

Dealers technicians are only human and they have learning curve.
Just got a message from fellow owner that his local dealer had no clue the 7-sp fills up from the bottom and even he went there asking for specific fill adapter, they stare at him like he come from Mars.
I don't know how cmriv can diagnose sbc pump condition with his computer, but I spend some time with high-tech technician playing with diagnosis - all we found is pedal count and pump activation count. When those 2 counts let you predict upcoming required maintenance, don't see how they can prevent failure.
And failure will happen. Again, I am trying to keep count and in all the years there have been less than 20 reported SBC failures that I read about on the forums.
This can be big number for some, or small for others.
Firestone did not recall their tires in 2000 till 46 people die in tire blow accidents.
Coming to testing car condition, when mentioned technician run simulated compression test that in 10 seconds, measuring starter load gave me idea of engine condition - my jaw drop to the ground.
Doing it the oldfashion way might be more accurate, but would take most of the day.

StarvingArtist

That is cool! First I've heard of it.

cmriv

SDS and Xentry tell you how close you are to threshold. There is a limit for the pump and the diagnostic equipment is able to decipher how close or far, within reason, you are to threshold. It may not give you a time date and location but it will give you some accurate numbers. It's the same thing as a brake pad and pad wear sensor. You can physically look at pad and determine okay, i can get another 2-3k out of my pads before the light cuts on. Yes, the pad warns you before it is actually fully worn out but sbc does the same in a sense, difference is sbc is hydraulic and electrical and there is alot that can get missed in between. Can physically look at a sds tablet screen and determine about how long pump will last within reason.


Freeze frame data in a short test under ESP/SBC will be able to determine, in the event of a death, whether the pump did it's job or not. Esp will be able to tell you exactly when brake pedal was depressed, pressure at each wheel, wheel speed, steering angle ect. So if in fact someone was killed a diagnostic on the vehicle will be able to decipher what vehicle was doing during the crash event. Freeze frame data is legit, tells you every minute detail about a control unit and when a fault occurred.


I'm not trying to defend SBC by any means but there are so many sbc equipped vehicles and owners who either have never had issues or deal with it when a issue occurs, and that number outweighs the number of failed units and doesn't justify the terrible design but it truly is a double edged sword.. It's a poor design and lasted for a short time, sorta, in select models. It doesn't give you a fair warning at all when it fails out of no where but customers have all the resources to find out what kind of shape the pump is in, whether it be a independent with the correct diag equipment or a stealership.


As for the new owner who sees no records of a sbc check, this can be for various reasons. Quality of dealership, technician capabilities and customer complaints. I'm not going to sit here and act like i check threshold on every sbc vehicle i work on but i will say i'm not hooking a computer up and running diagnostics for free. post your vin of your vehicle because i find it highly doubtful that a w211 with sbc and 82 service visits and not once having issues with sbc, possible? YES. Likely, NO! haha.


But why were you going 70mph through an intersection with a stop light?

mishar

I was not at 70 mph when SBC failed. That was the other guy. He was driving 70 mph because he couldn't brake. His SBC dacided to stop working without warning.

Your idea that reagular SBC maintenance can help has no sence. If therre is data stored saying that the threshold is near why wouldn't there be warning before it fails, or this is designers way to punish negligence by deth?

Your number game has no sense either. Driving a car is not bingo. Even a smallest chance that brakes fail without warning is unexceptible.

hangit06

Any system can fail on any automobile. The issue with the SBC is that it apparently will fail without warning due to the computer shutting it off, not because of a mechanical issue. See attached MB document.

If the system can be interrogated, then the dealer should have the ability to recommend the SBC unit be replaced.

John