I have a 2016 C450, I installed a Vivid ECU tuning box piggyback a month after I got the car last August and it has run great. I had my service A due a few weeks ago so i removed the box before I took it in. After I got it back I reinstalled the box and took it out for a spin and all was good. I started it up again and took took it for another drive and it threw another CEL. I pulled the battery for 30 min and it cleared the CEL but it came back after another drive. I am curious if there might of been a software update that was applied during the Service A that might be conflicting with the piggyback. I have an email out to Vivid but I figure I would reach out here as well.

 

What's wrong with the vivid tuning box?

 

Plutoe is a purist and looks down their nose at the plebs who modify a car. Yet he joined a forum where people talk about modifications.

But I agree with him on this. Sell the box. What's wrong with it? It apparently causes check engine lights.

 

I reset all of the connections and it went away. I am all about getting more out of the car so I am open to a different ecu/piggyback.