SPN 2659 FMI 13Aftertreatment
Aftertreatment 1 Diesel Particulate Filter Lamp - Out of Calibration
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Overview
Fault Code
SPN 2659 / FMI 13
Category
Aftertreatment
Derate Risk
No
Regen Inhibit
No
Inducement Risk
No
Component Location: The DPF warning lamp is located in the instrument cluster on the vehicle dashboard.
Common Symptoms
- DPF warning lamp illuminated on dash
- DPF regeneration lamp stays on continuously
- DPF lamp does not illuminate during key-on bulb check
- Intermittent DPF lamp operation
- Check engine light may be present
Root Causes
- ACM software/calibration file mismatch or outdated calibration Incorrect DPF lamp output signal calibration in ACM parameters ACM module replaced without proper calibration transfer Corrupted or incomplete calibration data in ACM memory Incompatible ACM hardware paired with mismatched software version Failed or interrupted ECU flash/reprogramming event
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Derate Behavior
Power Derate
No
System Interactions
SPN 2659 FMI 13 interacts with the following systems and may trigger cascading faults if not resolved promptly.
DPF differential pressure monitoring — soot load calculations affected
SCR NOx conversion efficiency — DEF dosing strategy may be altered
Active regen inhibit logic — regen may be blocked or delayed
Engine protection derate — ECM may reduce power to protect components
Common Diagnostic Mistakes
Replacing the sensor without verifying wiring continuity and supply voltage first.
Clearing codes without identifying and resolving the root cause — the fault will return.
Ignoring related active faults — cascading faults often share a root cause.
Skipping the connector inspection — corrosion and damaged pins are a leading cause of sensor faults.
Condemning the ECM before exhausting all wiring and component tests.
Replacing the DPF without verifying the regen system is functional — a failed regen injector will reload the new DPF.
Ignoring DEF quality — contaminated DEF causes SCR efficiency faults that look like hardware failures.
Related Faults in This Category
OEM System Resources
ASE Training Resources
Diagnostic Engine v7.0
Related Diagnostic Articles
Deep-dive diagnostic page: SPN 2659 FMI 13 — Full FSM Sequence & Repair Steps — includes wiring notes, sensor specs, and gated repair procedures.
Authority References
Diagnostic procedures on this page are informed by OEM service literature and industry standards.
EPA Aftertreatment & Emissions GuidelinesU.S. EPA heavy-duty diesel aftertreatment compliance, DPF/SCR regulations, and NOx standards.Cummins QuickServe OnlineOfficial Cummins service manuals, fault code lookup, and TSB database.Detroit Diesel DiagnoCentralDetroit Diesel diagnostic procedures, DDDL documentation, and service literature.PACCAR MX Engine ServicePACCAR MX-11 and MX-13 engine service documentation and DAVIE diagnostic guides.Volvo/Mack Tech ToolVolvo and Mack engine fault code reference and PTT/Tech Tool diagnostic procedures.ASE — Diesel Truck Technician CertificationNational Institute for Automotive Service Excellence — T2 Diesel Engines certification standards.
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