Cummins Fault Code
Free · no signupSPN 3251 FMI 00
High Soot Level / Forced Regen Locked
System
Emissions / Exhaust
Symptom
High Soot Level / Forced Regen Locked
Diagnosis & fix steps
LOGIC: DPF Differential Pressure Very High (Severe).
ACTION: Measure delta pressure using a mechanical gauge to confirm high soot load. If actual pressure is high, remove DPF for off-machine thermal cleaning or replacement.
Red Seal field insights
Prevents auto-regeneration due to fire hazard if soot mass exceeds critical thresholds. Performing forced regens at this stage can melt ceramic substrate.
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