Hi Everyone,

Just sharing my experience in getting rid of the SBC C249F warning message (Service Brakes - Visit Workshop). Before anyone starts off warning me of the dangers of suppressing the warning, I realize what I am doing. This is meant for people who have decided to go through it anyway.

I started off by buying the SBC programmer tool from Aliexpress (search for SBC W211, I got the one listed for about 28 USD, they are all the same). The tool arrived, however it would not do anything.

Link to supplier:
http://www.aliexpress.com/item/Promo...248422740.html


After debugging on the oscilloscope, it turned out one chip (MC33290) was fried (probably due to ESD). Replacing it with the pin-to-pin equivalent MC33660 chip did the trick!

1. Connect programmer to car while turned off. Wait for beep.
2. Turn key to ON (dont start car).
3. Press the programmer button of your choice (I went with 50%).

After about 10-15 seconds with intermittent red errors on the dash regarding disabled brakes and ESP, the programmer made 3 beeps and it was done. At that point I was left with an ESP error. Turning the key to the OFF position, removing the programmer, and starting the car did the trick.

I can confirm the programmer works and I would hate for one to pay lots of money for the same SBC "repair service", while you can do it yourself pretty cheap.

The programmer only programs the number of brake presses. Should the SBC unit experience real signs of wear (ex: long pumping time), the warning will definitely come back.

That's all folks.
Enjoy your W211 !

 

Thanks great post, I was always curious to know if one of those SBC programmer tools actually worked and cleared the SBC C249F warning message.

 

Are you saying that the chip on the tool was fried ?

 

Yes it sure was. I suspect it's just my unit. The QA on such devices is not the best for sure.

 

Dont worry, I'm 29!

I do have solid electronics experience, that's why I was able to fix the unit.

Symptoms were a non-responsive unit (no response to any key presses). The chip requires no programming. Only the main micro on board is flashed.

For the electronics tinkerers out there:

The main micro is using the TX/RX lines of the replaced chip also as input lines to the push buttons (kind of stupid, if you ask me). The fried chip was pulling its TX input pin low, which doubles as the GPIO of the 50% button. The micro was then thinking that the 50% button was continuously pressed.


Happy hacking.

 

So, all that is needed is this tool?

What's the deal with the included PC disc? Do you need a laptop to be in the car with you when this is being done?

No need for any other programs like DAS Xentry for this tool to work?

 

Yep, tool is all what is needed.

CD is useless and contains the same crap auto-translated text on the item description in the online shop.

No laptop needed. Just connect it to the OBD under the steering wheel and push the button of choice.

Regards

 

Is it possible that the C249F is disabling the SBC from building pressure in Accumulator causing the C2131. This happened after removing SBC and putting it back on and trying to bleed it. The c2131 will not go away even after swapping accumulators. I purchased the tool from China and it should be here tomorrow. Will it clear the C249F even if there is another error code?

 

Interested in any updates... got a list of codes and wondering if this little magic box will help.

 

If you just want to reset the sbc unit counter they work I purchased one 12 months ago and it reset without a problem. I also purchased a tool to service the breaks that opens the calipers and resets the sbc system, all avaliable on ebay.

 

Will this device clear the red brake message on my dash?

 

The red message relates to a real fault inside the SBC, not just a usage indicator warning.

I would definitely here have it properly repaired before driving (SBC replacement).

 

SBC unit (Rebuilt) $949.99 eeuroparts.com. $340 installation at my local Independent Mercedes-Benz Repair Shop.

 

Safety and driving without shaking hands PRICELESS

 

UPDATE: So I decided to take a gamble and place an order for the SBC reset tool. This device was able to clear code C249F and remove the red warnings from my instrument cluster panel but I still have a fault code that tells me the SBC motor is bad. It buys me time though, so I can save money for a new pump replacement.

 

SBC motor is bad and you have time?
What am I missing?

 

Time is not on your side. Your SBC should be replaced before you injure yourself or others when your brakes fail.

 

The tool works. Thank you...I'm well aware of the risk

 

I guess "time" was on my side after all. hahahahaha!!

 

So this tools are just to reset the brake press times?
I had an SBC failure the 1st week when I bought the car, however I've never had it again. Just turned off the car for a few hours and it never came back again, I thin it's because the car was parked for a long time, now I'm using it as a daily driver.

 

Yes. It will only clear code C249F. In my case it turned out I was also getting code C2129: Faulty Pressure Reservoir.

 

I've been looking for a recovery tool for the.cls500. I see the w211 recovery by OBD. Does anyone know if this is compatible with the cls500 or if there is another tool for the cls500.

 

cls is basically an E-class with with a different style. It’s the same.

 

If you are in the USA, the SBC warranty was extended to 25 years and unlimited mileage. Dealer will replace as needed. Search as it has been discussed multiple times on this site, particularly in the W211 AMG sub-forum.

 

I just order the recovery tool and should be getting it in a few days! I hate that message 😡😡