SPN 1220 FMI 0Engine Control
Series Throttle Control System - Forced Engine Shutdown
Scan Tool — in guided session
DVOM Testing — in guided session
Connector Pinout — in guided session
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Overview
Fault Code
SPN 1220 / FMI 0
Category
Engine Control
Derate Risk
Yes
Regen Inhibit
No
Inducement Risk
No
Component Location: Throttle actuator is mounted on the intake manifold or air inlet system near the engine intake.
Common Symptoms
- Engine shutdown immediately or within short time period
- Engine will not restart or starts and shuts down again
- Check engine light illuminated
- Throttle position sensor or pedal position sensor fault codes present
- Loss of throttle response before shutdown
- Multiple throttle-related fault codes active
Root Causes
- Faulty throttle actuator or throttle position sensor Wiring harness damage or connector corrosion in throttle control circuit ECM internal fault or software calibration issue Throttle body mechanical binding or contamination Loss of power or ground to throttle control system
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Derate Behavior
Power Derate
Yes
System Interactions
SPN 1220 FMI 0 interacts with the following systems and may trigger cascading faults if not resolved promptly.
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 1220 FMI 0 — 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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