SPN 5585 FMI 31 — Engine derate active — parent fault
What it means: Engine derate active — parent fault.
How serious / can you keep driving: Caution. Limp to the next safe stop.
Check first: Find parent fault
Don't risk it — look up listed providers near you and give them this SPN/FMI when you call.
Listed providers in and near Houston, TX
Providers based in Houston first, then nearby providers by distance. Tell them SPN 5585 FMI 31 and what the truck is doing. RoadService.app lists these providers and does not employ them or carry out the repair.
- 0.0 mi away — based in Houston, TX · (832) 377-0578
- 0.0 mi away — based in Houston, TX · (713) 219-9090
- 0.0 mi away — based in Houston, TX · (713) 671-9751
Applies to: Detroit · Navistar · Paccar · Volvo
What SPN 5585 FMI 31 means
Engine derate active — parent fault.
How serious is it?
Caution. Limp to the next safe stop.
Most likely causes
- Parent fault commanding derate
- Parent fault
First moves (roadside)
- Find parent fault
- Find parent
FAQ
Engine derate active — parent fault.
Caution — Limp to the next safe stop.
The most common cause is: Parent fault commanding derate. Other possibilities include Parent fault.
Limp to the next safe stop. When in doubt, get a qualified mobile diesel tech on the truck before continuing.
Related codes
Codes that commonly appear alongside SPN 5585 FMI 31, or share the same subsystem.
- Engine Protection — Power Derate Active (SPN 1569 FMI 31)
- Intake Manifold (Charge Air) Temp — High (SPN 105 FMI 0)
- Turbo Boost Pressure — High / Overboost (SPN 1127 FMI 16)
- Boost pressure high (SPN 102 FMI 0)
- Boost sensor — voltage low (SPN 102 FMI 4)
- Intake manifold temp — voltage high (SPN 105 FMI 3)
- Intake manifold temp — voltage low (SPN 105 FMI 4)
- Injection control pressure low (HEUI — older engines) (SPN 164 FMI 1)
Same symptom: Power derate
Other codes that stage a derate. The clock starts when the lamp does.
- SCR Operator Inducement — Severe Derate Active (SPN 5246 FMI 0) · Aftertreatment & Emissions
- Engine Coolant Temperature — Too High (SPN 110 FMI 0) · Cooling
- DPF Differential Pressure — Data Erratic (SPN 3251 FMI 2) · Aftertreatment & Emissions
- DEF Dosing Unit — Not Responding Properly (SPN 3361 FMI 7) · Aftertreatment & Emissions
- DEF Quality — Out of Spec (SPN 4094 FMI 31) · Aftertreatment & Emissions
- SCR Conversion Efficiency — Below Threshold (SPN 4364 FMI 18) · Aftertreatment & Emissions
Find a mechanic or related guides
General diagnostic guidance for heavy-duty diesel engines (Cummins, Detroit, PACCAR, Volvo, Mack). Not a substitute for a scan-tool diagnosis on your specific truck.