The powertrain control module has detected that the differential pressure across the diesel particulate filter on bank 2 is lower than expected, indicating a restriction or sensor fault.
Excessive soot or ash buildup in the DPF on bank 2 restricts exhaust flow, lowering measured differential pressure.
Blocked or collapsed exhaust pipe, muffler, or upstream components can reduce pressure differential readings.
A damaged or contaminated pressure sensor or its wiring can give an incorrect low‑pressure signal.
If the DPF has not been regenerated properly, soot accumulation can cause low pressure conditions.
Corroded, loose, or damaged electrical connections can interrupt sensor signals.
A malfunctioning PCM is possible but uncommon; it is considered only after other components are verified.
Replacing the PCM is rarely necessary; the code is usually caused by a clogged filter, sensor fault, or exhaust restriction that should be diagnosed first.
Yes, a blocked or heavily sooted DPF on bank 2 is the most frequent cause of this code.
Performing a forced regeneration can restore proper DPF function and may clear the code if the issue was an incomplete regeneration.
Yes, damaged or loose wiring to the pressure sensor can produce a false low‑pressure signal and trigger the code.