Emissions
I'm sure by now you have rectified the issue. I also had the same issue after disconnecting and reconnecting my battery. If you already don't have an ODB scanning tool, do yourself a favor and buy one. I invested $100 dollars via Amazon for the BlueDriver Bluetooth scan ODB scanning tool that works with my smart phone. It works for many vehicle car manufactures including most Mercedes. I have a 2006 CLS 55 AMG and it worked for me. In the ODB scan smog scan test option, it revealed Evap not complete. After some on-line research, I found this useful information on the internet regarding "drive cycle for incomplete readiness" for Mercedes emission testing.
https://justsmogs.com/2016/06/merced...ed-smog-check/
In my case, I went directly to step number 7 making ensuring my fuel level was between 1/4 to 3/4 full. I started the car and allowed it to idle for 20 minutes. I ran the scan for Smog using my scanning tool and it was completed. Emission tested and it passed.


