Thank you all for your kind messages
As an update; taken to main dealer (i know; more self-flagellation) and diagnosed as failing ESP/ABS control module. £1700 replacement cost. They are '95% sure' that this will fix the issues - they have found overvoltage codes localised to that module.
Dear all
My w204 m274 C180 is causing me endless headaches
On (almost) every time the car has been started up and then driven off, as soon as it reaches approx 20 mph:
- All dash lights flash
- power steering cuts out for a few seconds
- car thinks handbrake is still on and makes assoc...