SPN 3712 FMI 18 — SCR inducement — stage 3 (severe derate)
What it means: SCR inducement — stage 3 (severe derate).
How serious / can you keep driving: Caution. Limp to the next safe stop.
Check first: Fix parent
Don't risk it — look up listed providers near you and give them this SPN/FMI when you call.
Listed providers nearest Billings, MT
Closest first. Tell them SPN 3712 FMI 18 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 Billings, MT · (406) 245-8985
- 0.0 mi away — based in Billings, MT · (406) 252-8413
- 0.0 mi away — based in Billings, MT · (406) 780-3711
Applies to: Detroit · Sae · The dreaded 5 MPH limp
What SPN 3712 FMI 18 means
SCR inducement — stage 3 (severe derate).
How serious is it?
Caution. Limp to the next safe stop.
Most likely causes
- Parent fault unaddressed — final stage
- Parent SCR fault unaddressed
First moves (roadside)
- Fix parent
- Clear via OEM tool
- Clear via DiagnosticLink
FAQ
SCR inducement — stage 3 (severe derate).
Caution — Limp to the next safe stop.
The most common cause is: Parent fault unaddressed — final stage. Other possibilities include Parent SCR fault unaddressed.
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 3712 FMI 18, or share the same subsystem.
- SCR operator inducement — stage 1 (warning only) (SPN 3712 FMI 15)
- SCR inducement — stage 2 (25% torque reduction) (SPN 3712 FMI 16)
- SCR inducement — stage 3 (severe torque derate) (SPN 3712 FMI 17)
- SCR inducement — condition exists (SPN 3712 FMI 31)
- SCR Operator Inducement — Severe Derate Active (SPN 5246 FMI 0)
- Aftertreatment 1 Diesel Particulate Filter Differential Pressure - Data Valid But Above Normal Operating Range, Most Severe Level (DPF severely restricted / plugged) (SPN 3251 FMI 0)
- Aftertreatment 1 Diesel Exhaust Fluid Quality - Data Valid But Below Normal Operating Range, Most Severe Level (DEF quality/concentration incorrect) (SPN 4364 FMI 1)
- DPF Differential Pressure — Data Erratic (SPN 3251 FMI 2)
Same symptom: DEF / SCR fault
Other codes in the DEF and SCR chain — the ones that end in an inducement countdown.
- Reductant System Performance Bank 1 (P204F) · Aftertreatment & Emissions
- Reductant Quality Deviation (P20EA) · Aftertreatment & Emissions
- DEF tank level low (SPN 1761 FMI 18) · Aftertreatment & Emissions
- DEF tank temp sensor — voltage high (SPN 3031 FMI 3) · Aftertreatment & Emissions
- Upstream NOx sensor — internal failure reported (SPN 3216 FMI 12) · Aftertreatment & Emissions
- SCR inlet NOx sensor — erratic (SPN 3216 FMI 2) · 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.