SBC programming experience
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 !
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.
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?
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
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Last edited by Gangrene3075; Apr 7, 2016 at 08:37 PM.
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.






