Mercedes Vito 108 cdi 2002 reg 122000 miles - EDC warning light - Mercedesfrustration

Hi, New to HJ . I have owned my Vito 638 108 cdi for 4 years and has been great until last year when it developed a problem with speedo which I sent away to have it repaired and then another issue which kept putting it into limp mode now and then. Eventually solved that after many sleepless nights and a couple of sessions of warping the plastic. But now on my way to work last night it just stopped dead displaying EDC in red on dash (Serious I thought ) After a few attempts to restart I gave up and phoned the A A ( breakdown service not the other one even though I felt like it) After an hour and a bit they eventually turned up and it just started. Has anyone had the same problem or similar and solved it ? Please let me know. I am slowly losing faith in my Vito as the more I read about them the more faults they seam to have.