Hello
SBC not 100% what it stands for but on most auto's you stop at the lights and you keep your foot on the brake.
With SBC on these models you stop, press the brake down then again and it holds it, you can then rest you foot on the accelerator pedal (makes for a quick start...)
Or you can use the cruise stalk to activate de activate...
I rarely used it but my dad loved it.
My Dad bought a E320CDi S211 new in 2003, his car has this SBC, three years ago I bought this car off him and only recently just swapped it for a ML.
Best car we have ever owned, 40mpg plus on any longish journey. fits anything almost in the boot, very comfy to do big miles in. This car has blasted to Europe probably over 30 times, carried and towed all manor of stuff. However it was looked after and serviced regularly.
In the time we had it apart from tyres and brakes it needed two springs (front), oh and I sold it on 135,000 and I spoke to the current owner who said its now on 150,000 and just needed a water pump.
When I had it I also changed the wheels a few times for looks and fitted a Brabus D6 box which seem to make it even more economical and pretty nippy !!
Really is a good car, I don't know what SBC fault will cost or indeed if it can be reset? It never caused me an issue. The other thing you will find googling is the radiator depending which one can cause issues???
Too be honest spend enough time on line on forums and googling and you would put yourself off buying any car.
My old one (on 135,000 miles)