Hello , thanks for your question in the autoaid Community.
Your described fault Code means: Check C249F working life of the component A7/3 (SBC hydraulic unit)
This is a fault Code that means your Hydraulic Component (SBC) is at its life end.. by these fault Code you have to go to your Daimler dealer and there must the SBC checked with the Star Diagnosis. By these check, the mechanic could see if there must the Software replaced or the SBC has to be replaced. Sorry this isn´t cheap, but this is the correct way for this type of failure.