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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.
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.
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!
!
Are you saying that the chip on the tool was fried ?
Be carefull with this one---you will notice that for most of us schleps we would have tried the unit and it failed therefore we would have returned the unit---My point is that is what did NOT happen--the poster had to determine what was wrong and used an oscilloscope to do so, an instrument we all have access to and of course can use.
Then it was determined that a chip was faulty, not only did he have the hardware to remove and replace the chip, his experience determined that a different chip was applicable---I also assume he had to flash the new chip---a task that every weekender on the forum can do!!
All this on a 28 USD unit--a huge overkill---now if the OP is in diapers then I would say WOW,but!!
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.
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?
I SAS hope this is your car and not a customers-------the so called tool only reads the specific chip within the control module and either clears the number of times the brakes have been applied or overwrites the actual value with 000000.
I doubt the tool will clear additional faults, except possibly the dependent ones. The only way you will know is when you use the tool to reset the brake actions
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.
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.
Last edited by Gangrene3075; 04-07-2016 at 08:37 PM.
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.
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.
03-11-2015, 06:29 PM
