Stabilisation fault

[Lifly]

Hi can any one help. 
I have an Audi A1 sline 2 litre diesel. 
Intermittent fault on dash says stabilisation fault, with light for traction control on and headlights defect. This happens intermittently and sometimes  will not start at all completely dead, take key out of ignition and back in starts fine. 
been to an Audi specialist and fault was ecu unit. This has been changed and still the same, anyone have had this problem? Any help would be appreciated