International (Navistar)
J1939 SPN/FMI
SPN 3031 / FMI 3
International Fault Code SPN 3031 FMI 3: Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature 1: Voltage Above Normal, Or Shorted To High Source
SPN 3031 FMI 3 on International / Navistar trucks means: Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature 1: Voltage Above Normal, Or Shorted To High Source. The failure mode (FMI 3) is “voltage above normal, or shorted to high source”.
Code details
- Manufacturer
- International (Navistar)
- Applies to
- International A26 (2024–2025)
- Fault code
- SPN 3031 FMI 3
- J1939 SPN
- 3031
- FMI
- 3 — Voltage above normal, or shorted to high source
- Truck models in source
- 3200, 4100, 4300, 4400, 7300, 7400, 7500, 7600, 7700, 8500, 8600, BE 200, CE Bus, CXT, DuraStar, LoneStar, MXT, ProStar, RXT, TranStar, WorkStar
What to do next
- Read active and inactive codes with the OEM service tool (Diamond Logic Builder can clear previously active codes) and note the occurrence count.
- FMI 3 tells the shop the type of failure to test for: voltage above normal, or shorted to high source.
- Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.
Get this code diagnosed
Send one request and nearby diesel shops and mobile mechanics can quote the repair.
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Related fault codes
- International Fault Code SPN 3031 FMI 13 — Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature 1: Out Of Calibration
- International Fault Code SPN 3031 FMI 2 — Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature 1: Data Erratic, Intermittent Or Incorrect
- International Fault Code SPN 3031 FMI 20 — Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature 1: Data Drifted High
- International Fault Code SPN 3031 FMI 4 — Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature 1: Voltage Below Normal, Or Shorted To Low Source
- PACCAR Fault Code P3895 — DEF Tank Temperature Sensor – Short Circuit to Supply or Open Circuit
- PACCAR Fault Code P3899 — DEF Tank Temperature – Data Erratic, Intermittent or Incorrect
- PACCAR Fault Code P3900 — DEF Tank Temperature Sensor – Voltage Too Low or Short Circuit to Ground
Source: International A26 2024–2025 fault code list (Diesel Laptops). See also OBD-II codes.
