Truck Fault Codes

International A26 SPN 1569 FMI 31 �?Engine Protection Torque Derate Active

SPN 1569 FMI 31 on an International A26 means the engine protection system is actively derating torque. This is a secondary code �?check companion active codes in International Diamond Logic to identify the trigger: SCR inducement, coolant temperature, oil pressure, or DPF loading.

Code Details

Structured details for SPN 1569 FMI 31
Display codeSPN 1569 FMI 31
SPN1569
FMI31
OEM codeNone listed
ManufacturerInternational
SystemEngine protection / aftertreatment
ComponentEngine control module �?protection strategy
Source addressUnknown or not applicable
Severityhigh
Review statussource backed
Source confidencemedium
Last reviewed2026-06-11

Plain-English Meaning

The International A26 ECM reduces engine power when any critical parameter crosses a protective threshold. SPN 1569 FMI 31 confirms a derate is occurring, but the companion fault codes explain why. Resolve the companion codes to clear the derate. On International LT Series, RH Series, and HX Series trucks, the A26 SCR inducement system uses Diamond Logic to enforce EPA compliance. ServiceMaxx displays the inducement status, counter distance, and all active fault codes contributing to the derate. The required repair sequence is: verify DEF quality, confirm dosing system function, and assess SCR catalyst efficiency. ServiceMaxx resets the inducement counter after the root causes are confirmed resolved.

SPN 1569 is the Engine Protection Torque Derate parameter in J1939. FMI 31 indicates an active derate on the International A26 engine management system. Common triggers include SCR inducement reaching the derate stage, high coolant temperature, low oil pressure, and critical DPF soot loading. International Diamond Logic provides all active codes and protection event history needed for diagnosis.

Common Symptoms

  • Noticeable power reduction during operation
  • Possible vehicle speed limitation
  • Check engine or protection warning lamp active
  • Multiple companion fault codes in Diamond Logic

Possible Causes

Possible causes may include the items below. The list is not a parts diagnosis.

  • SCR or aftertreatment inducement reaching the derate stage
  • High coolant temperature from a cooling system fault
  • Low engine oil pressure
  • Critical DPF soot overload
  • Multiple simultaneous faults triggering the protection strategy

First Checks

  • Connect International Diamond Logic and review all active fault codes to identify the primary trigger
  • Check coolant level, oil level, and DEF quality as quick baseline checks
  • Resolve the underlying cause �?SPN 1569 FMI 31 clears when the triggering parameter normalizes
  • Do not clear the fault without addressing the root cause
  • Connect ServiceMaxx and identify all active fault codes alongside the inducement status
  • After resolving root causes, use ServiceMaxx to reset the aftertreatment inducement counter

Can I Keep Driving?

The A26 is derated while this fault is active. If the trigger is a cooling or lubrication issue, continued operation risks engine damage. If aftertreatment-related, the derate deepens with additional distance.

SPN 5246 FMI 31Aftertreatment �?SCR system · SCR catalyst / NOx sensorsSPN 3364 FMI 1Aftertreatment �?DEF system · DEF quality / concentration sensor

Related Lookup Pages

Sources

  • International Trucks Service Support Public Resources International Trucks / Navistar International · oem · accessed 2026-06-11 · confidence medium

    Source: International Trucks / Navistar International, International Trucks Service Support Public Resources. This page paraphrases factual fields only and is not a substitute for the original document.

    Open source
  • Navistar Engine Diagnostic Trouble Code Body Builder References Navistar / International Truck Body Builder · oem · accessed 2026-05-05 · confidence medium

    Source: Navistar / International Truck Body Builder, Navistar Engine Diagnostic Trouble Code Body Builder References. 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

How does the International A26 engine protection derate compare to the MaxxForce 13?

The A26 uses a more conventional aftertreatment-based protection architecture compared to the MaxxForce 13. The SPN 1569 FMI 31 derate mechanism is standard J1939 across both engines, but the A26's protection triggers are more aligned with current industry practice rather than the high-EGR, early-SCR-delete approach of some MaxxForce configurations.

Can International OnCommand diagnostic portal identify SPN 1569 FMI 31 remotely?

Yes. Navistar's OnCommand Connection telematics system transmits active fault codes to the fleet management portal. SPN 1569 FMI 31 would appear as a high-priority active fault. The OnCommand portal can also help locate the nearest International dealer for service.

Is it safe to drive an International LT with SPN 1569 FMI 31 active to the nearest dealer?

Whether it is safe depends on the companion code triggering the derate. If the trigger is an aftertreatment issue and the engine is running smoothly with no other warning, a short drive to a dealer may be acceptable. If the trigger is a cooling or oil system fault, stopping promptly and assessing the condition before continuing is the safer approach.