Code Details
| Display code | SPN 1569 FMI 31 |
|---|---|
| SPN | 1569 |
| FMI | 31 |
| OEM code | None listed |
| Manufacturer | Ford |
| System | Engine protection / aftertreatment |
| Component | PCM engine protection strategy |
| Source address | Unknown or not applicable |
| Severity | high |
| Review status | source backed |
| Source confidence | medium |
| Last reviewed | 2026-06-11 |
Plain-English Meaning
The Ford 6.7 Power Stroke PCM continuously monitors critical engine parameters. When any parameter �?such as DEF level, coolant temperature, or engine oil pressure �?crosses a protective threshold, the PCM reduces engine power to prevent damage or emissions violations. SPN 1569 FMI 31 is the notification that a derate is active. The actual problem is identified by the companion codes.
SPN 1569 is the Engine Protection Torque Derate parameter. FMI 31 indicates a condition is present requiring a derate. On Ford 6.7 Power Stroke PCM calibrations for model years 2011 to present, the derate triggers include DEF low or empty, SCR efficiency below threshold, DPF critical soot loading, high coolant temperature, and oil pressure. Ford IDS provides the full fault tree and protection event log.
Common Symptoms
- Noticeable reduction in engine power and torque
- Wrench light on the instrument cluster
- Diesel exhaust fluid warning if DEF is the trigger
- Multiple companion codes in Ford IDS
Possible Causes
Possible causes may include the items below. The list is not a parts diagnosis.
- DEF tank empty or DEF quality failing, triggering SCR inducement derate
- DPF soot overload requiring regen that has not been able to complete
- High coolant temperature from a cooling system fault
- Low engine oil pressure warning
- SCR system fault (catalyst efficiency, NOx sensor, or dosing injector failure)
First Checks
- Read all active DTCs with Ford IDS or an OBD2 scan tool capable of reading J1939/heavy-duty codes
- Check DEF tank level and quality �?top off with ISO 22241 DEF if low
- Check coolant level and oil level immediately
- Do not attempt to clear codes and drive without addressing the companion code root cause
Can I Keep Driving?
The vehicle is operating in a reduced-power protection mode. If the trigger is a cooling or lubrication fault, stop operation and diagnose before continuing. If aftertreatment-related, resolve the trigger before the derate deepens.
Related Codes
Related Lookup Pages
Sources
- Ford Trucks Service Support Public Resources Ford Motor Company · oem · accessed 2026-06-11 · confidence medium
Source: Ford Motor Company, Ford Trucks Service Support Public Resources. This page paraphrases factual fields only and is not a substitute for the original document.
Open source - SAE J1939 Standards Collection SAE International · official · accessed 2026-05-05 · confidence medium
Source: SAE International, SAE J1939 Standards Collection. This page paraphrases factual fields only and is not a substitute for the original document.
Open source
FAQ
Can a Ford F-350 with a 6.7 Power Stroke drive in limp mode to a shop with SPN 1569 FMI 31 active?
Whether it is safe to drive depends on the companion code trigger. If the derate is from a DEF or aftertreatment issue and the engine runs smoothly with no temperature warnings, a short drive to a service facility may be acceptable. If coolant temperature is high or oil pressure is low, stop immediately. Always read the companion codes first to assess the risk.
Does the Ford 6.7 Power Stroke enter a 5-mph limp mode for SCR failures?
The Ford 6.7 Power Stroke uses a progressive inducement strategy for SCR and DEF faults. In the final stage �?when DEF is depleted or DEF quality has been failing for an extended period �?the PCM can reduce vehicle speed to a very low limit until the condition is resolved. This is intended to enforce compliance with federal emissions regulations. Maintaining adequate quality DEF prevents this outcome.
Can I delete the DEF system on a Ford 6.7 Power Stroke to prevent SPN 1569 FMI 31?
Emissions system tampering on vehicles operated on public roads is illegal under federal law (Clean Air Act Section 203) and can result in significant fines. Beyond the legal implications, DEF system deletes void the powertrain warranty and can cause issues with commercial vehicle inspections. The correct resolution is to maintain the DEF system in proper working order.