X-Trail 2.2 YD ETi 2003 T30 - Can I get more than just ECMD

[Tom]

The DTCs usually clear once the issue is fixed and the error codes are cleared. The ECU must think there is still an issue if the DTC comes back.
Did you replace the DPF? Did you check if all the pressure sensors are connected?

[Jotuka1]

Thanks Tom! I did not replace the DPF, it's was cleaned and in good condition. The differential pressure sensor is connected but I can't really tell if it's working properly or not. While diagnosing using NDSII, I did not see any readings displayed for it. How can I test the differential pressure sensor using a multimeter and NDSII? Can NDSIII do a DPF reset? All looks fine to me, I'm still confused on what might be the issue!