DPF (Diesel Particulate Filter) issue is a common Mercedes Benz diesel problem.
This is a list of symptoms you may notice when there are issues with the DPF.
The 4S store will charge $1000-$2000 for the PDF regen. You can force Mercedes DPF regeneration with a professional diagnostic scanner such as Mercedes MB Star Diagnostic. Regeneration can be carried out with the vehicle driving or running but parked.
Our customer has tested VXDIAG Benz C6 scanner on Mercedes GLK W204 DPF Regen, save $2000.
A C6 VCI with latest 2019.09 Benz and BMW add-on software HDD loaded
Follow C6 prompts to perform PDF generation step by step
(On most MB Star Diagnostic scanners, DPF regeneration can be started by going to:
Control Units >
CDI Module >
Activation / Tests / Adaptations >
Manual DPF regeneration )
VXDIAG C6 Benz helps fix some other small problems and show wiring diagram of each modules as well.
It paid for itself already.