Bit late - but I just noticed your nice new C Class Merc!
These are a bargain atm. My son recently bought an E Class Estate for little money. They are FAB cars - he loves it!
Some years ago I got hold of a "Star Machine" so I could properly diagnose and service the wife's SMART Roadster. The "STAR machine" has diagnostics for ALL Mercs (and Mitsubishi) including all SMART, Merc Buses and Merc trucks ..and of course the E Class is on there too. The fact I already had a Star Machine influenced his decision to buy a Merc.
We looked at a few E Class before buying the best of the bunch ...he bought the one with no serious faults pending (unfortunately nearly all have some). The sellers (none were Merc Specialists) agreed to let us plug the STAR into the diagnostics port prior to a test drive- which benefited them too because they had no idea about what faults might be on their cars. Usually a diagnostic-only session would cost £100 at a Main Dealer - so the sellers saved a bit of money by allowing us to 'plug-in' before buying. One E class estate we looked at in Leeds had a list of faults as long as your arm!
Fortunately, the E Class my son did buy had just had a new Sensotronic Brake Control (SBC) unit fitted. Apparently, according to a Merc Specialist near us, the SBC unit is designed to FAIL after a set number of brake pedal presses (outrageous!
). I think there has been a recall on this fault? We had no idea about the SBC "design fault" at the time we bought the car - we were just lucky it had just been replaced. I don't know if the C class has the SBC - but I could find out by looking it up on the Star / EPC.
Also to bleed the brakes properly with an SBC fitted (every 2 years) you should do it with the Star Machine connected. The Star remotely operates valves in the SBC in order to systematically build pressure for a proper flush and bleed. Having the Star Machine is a bonus for any DIY Merc owner...otherwise you have to use a Merc Specialist sooner of later. Not an issue if that's what you set out to do, of course
Hope you have bought a good one Dave - they are very nice cars. But just like a lot of moderns they are both blessed and cursed by the presence of computerised electronic control systems