Home › Codes › SPN 1569 › FMI 31

SPN 1569 FMI 31

Engine Protection Torque Derate — Condition exists / not available.
A general 'this condition is present' flag, or the failure mode is not available. Many OEMs use it for status-type faults such as derates or inducements.

What the SPN covers: The engine has reduced its power on purpose to protect itself. More on SPN 1569.

What FMI 31 usually points to: Check what the SPN itself describes; the FMI simply says the condition is active. More on FMI 31.

Severity

HIGH — limit use, diagnose now

This is a result, not a cause. Find the other active code that triggered the derate.

Likely causes

  1. Overheating or low oil pressure protection
  2. Aftertreatment (DPF/SCR/DEF) problem
  3. Sensor fault the engine cannot trust

Checks & fixes (easiest first)

  1. Read all active codes — the root cause is usually another SPN
  2. Address aftertreatment codes such as 3719, 4364, 5246
  3. Check coolant and oil conditions

FAQ

What does SPN 1569 FMI 31 mean?

Engine Protection Torque Derate — condition exists / not available. A general 'this condition is present' flag, or the failure mode is not available. Many OEMs use it for status-type faults such as derates or inducements.

Is SPN 1569 FMI 31 serious?

This is a result, not a cause. Find the other active code that triggered the derate.

What should I check first for SPN 1569 FMI 31?

Read all active codes — the root cause is usually another SPN; Address aftertreatment codes such as 3719, 4364, 5246; Check coolant and oil conditions.