Particulate Trap Bank 1 P2002 00 [01100100] - Efficiency Below Threshold

[Tomekk]

In my Audi A3 8v, 1.6 tdi, 2016, CXXB engine I keep getting check engine over and over again with the "P2002 00 [01100100] - Efficiency Below Threshold" error. I had my dpf regenerated and checked, I tested my injectors - replaced one. I bought a new original vw differential pressure sensor, installed it - but got the negative pressure readings, error kept coming back, so I switched back to the old one as I could not find a way to run adaptation through vcds.

1. Can you please advice on how to perform a pressure sensor adaptation with vcds? Coding II is greyed out, adaptation menu list does not show any option for diff press sensor.

2. I visited many mechanics, but no one was able to solve the issue with recurring MIL.

3. soot mass measured shows negative value: how to fix this? maybe related to the sensor adaptation - no idea.

Thanks for help. vcds output below:

23960 - Particulate Trap Bank 1
          P2002 00 [11101100] - Efficiency Below Threshold
          MIL ON - Intermittent - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Priority: 2
                    Fault Frequency: 5
                    Mileage: 127048 km
                    Date: 2025.05.24
                    Time: 22:19:21

                    Engine speed: 1588.50 /min
                    Normed load value: 24.3 %
                    Vehicle speed: 69 km/h
                    Coolant temperature: 88 °C
                    Intake air temperature: 20 °C
                    Ambient air pressure: 980 mbar
                    Voltage terminal 30: 13.421 V
                    Unlearning counter according OBD: 40
                    Particle filter: air pressure sensor 1 bank 1: raw value: 13.5 mbar
                    Exhaust recirculat.2: different.press.sens.1 bank 1: raw value: 38.1 mbar
                    Par.fil: diff.pr.sens.1 bank 1: offset: 0.0 mbar
                    Particl.filt.: differential pressur.sensor 1 bank 1: dyn.offset: 1.4 mbar
                    Outside temperature sensor 1: B1: raw value: 12.0 °C
                    Particle filter: soot mass measured: -9.83 g
                    Particle filter: soot mass calculated: 7.34 g