Volvo All Engines (2010 Emissions) Fault Code: SPN 3251 FMI 4 PID: 81 Aftertreatment DPF Differential Pressure

The function identifies and indicates malfunction of the aftertreatment diesel particulate filter (DPF) by analyzing the pressure drop over the aftertreatment DPF. This is done by making a check for deviation between sensor value and a model pressure drop. In some extreme cases the engine will derate.

Conditions for diagnostic trouble code (DTC):
1) The voltage at pin A137:26 is less than 0.27?V

Diagnostic operating conditions
1) Ignition key in ON position

Observable symptoms
1) Regeneration not possible

Probable cause
1) Connector
2) Open circuit, Signal wire
3) Open circuit, Supply wire
4) Short circuit to ground, Signal wire
5) Wiring harness
6) Aftertreatment DPF Differential Pressure Sensor
7) Aftertreatment Control Module (ACM)