Check engine light is on.
Left front window is inoperative.
Engine oil is leaking under vehicle.
Inspect vehicle for needed services.

Diagnosis/ Work done:
Tested vehicle, codes P20C6 is present. Replaced left rear oxygen sensor and cleared codes, retested system, no codes are present at this time.
Tested and replaced left front door control module and programmed.
Tested and replaced oil level sensor.
Performed Mercedes Benz scheduled service “A”.
Replaced rear brake discs, pads and sensor.