My Volvo S80 D3 started to activate MIL with the P0420 error. According to VIDA this error is related to DPF system. Does anyone have experience in solving this error on a diesel engine?

VIDA says:
Diagnostic trouble code (DTC) information ECM-P042000Condition
The Engine control module (ECM) checks that the exhaust gas temperature upstream of the catalyst is considerably higher than downstream of the catalyst. The control module compares the temperature sensor signals between the temperature sensor particle filter and the temperature sensor catalyst.
The diagnostic trouble code (DTC) is stored if the control module detects that:

• The difference between the two temperature sensors' values is less than a pre-determined limit value.

The control module's test for the diagnostic trouble code (DTC) starts in the event of:

• Regeneration.

Note! The control module can only detect the fault once the test has been started and the diagnostic trouble code (DTC) is stored when the conditions are met.Substitute value

• None.

Possible source

• Damaged catalytic converter.
• Removed catalyst.

Fault symptom[s]

• Warning lights and chimes/Malfunction Indicator Light ("Check engine" light) indication/no indication
• Text window and warning symbol/Text message