International Fault Code SPN 3251 FMI 2: Aftertreatment 1 Diesel Particulate Filter Differential Pressure: Data Erratic, Intermittent Or Incorrect

Code details

Manufacturer

International (Navistar)

Applies to

International A26 (2024–2025)

Fault code

SPN 3251 FMI 2

J1939 SPN

3251

FMI

2 — Data erratic, intermittent or incorrect

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 2 tells the shop the type of failure to test for: data erratic, intermittent or incorrect.
• Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.

Related fault codes

• International Fault Code SPN 3251 FMI 2 — DPFDP Signal – Erratic, Intermittent, or Incorrect
• International Fault Code SPN 3251 FMI 0 — DPFDP Excessively HIGH (Plugged Filter)
• International Fault Code SPN 3251 FMI 10 — DPFDP Signal – Abnormal Rate of Change
• International Fault Code SPN 3251 FMI 14 — DPFDP Sensor Pressure Hoses Reversed
• International Fault Code SPN 3251 FMI 21 — DPFDP Excessively LOW (Sensor/Circuit Fault or Missing DPF)
• International Fault Code SPN 3251 FMI 3 — DPFDP Signal – Out of Range HIGH
• International Fault Code SPN 3251 FMI 4 — DPFDP Signal – Out of Range LOW
• International Fault Code SPN 3251 FMI 0 — Aftertreatment 1 Diesel Particulate Filter Differential Pressure: Data Valid But Above Normal Operational Range – Most Severe Level