I have a Vauxhall(Opel) Meriva 2011, bought it from a private seller a few months ago.. 1686 cc diesel, all history great.. and 2 days after we bought it we had multiple codes on the dashboard and multiple lights on! We took it to 3 mechanics and they all raise their shoulders. One tried, change the battery, headlight, paid a few hundreds .. codes disappear and then they come back and the car goes in limp mode, aircon doesn’t work, I have no idea what my speed is, the board gets bad .. the code is code 68 and on the dashboard are light up RED: electronic parking break, manual parking break / clutch fluid level, YELLOW ABS, electronic parking break degraded performance, service soon, power steering wheel failure. The mechanics all plugged in their computers and just don’t know what it is exactly and the thing is, it comes and then it goes for a long time. It gives me anxiety 🙁 please help. 
some error on their computer was : 

EPS 4 errors 

ENGINE 1 error 

PBCM 2 errors 

but nobody knows what’s actually wrong ..