SPN 512 FMI 10Engine Protection
Driver's Demand Engine Percent Torque - Abnormal Rate of Change
Scan Tool — in guided session
DVOM Testing — in guided session
Connector Pinout — in guided session
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Overview
Fault Code
SPN 512 / FMI 10
Category
Engine Protection
Derate Risk
No
Regen Inhibit
No
Inducement Risk
No
Component Location: The accelerator pedal assembly is typically mounted on the floor of the cab near the driver's feet with integrated position sensors.
Common Symptoms
- Engine hesitation or stumbling during acceleration
- Erratic throttle response or delayed acceleration
- Engine may not respond to throttle input changes
- Check engine light illuminated
- Intermittent loss of power during operation
- Engine surging or hunting at steady throttle
Root Causes
- Faulty accelerator pedal position sensor Intermittent wiring or connector issues in accelerator pedal circuit ECM software calibration issue Damaged or corroded accelerator pedal sensor connector Failed throttle position sensor signal validation
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Derate Behavior
Power Derate
No
System Interactions
SPN 512 FMI 10 interacts with the following systems and may trigger cascading faults if not resolved promptly.
ECM communication — J1939 network faults can affect all connected modules
Engine protection — ECM may trigger derate to prevent damage
Aftertreatment — engine protection derates can affect regen strategy
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.
Related Faults in This Category
OEM System Resources
ASE Training Resources
Diagnostic Engine v7.0
Related Diagnostic Articles
Deep-dive diagnostic page: SPN 512 FMI 10 — 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.
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.EPA Aftertreatment & Emissions GuidelinesU.S. EPA heavy-duty diesel aftertreatment compliance, DPF/SCR regulations, and NOx standards.
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