International Fault Code SPN 5743 FMI 9: Aftertreatment 1 SCR Temperature Sensor Module: Abnormal Update Rate

Code details

Manufacturer

International (Navistar)

Applies to

International A26 (2024–2025)

Fault code

SPN 5743 FMI 9

J1939 SPN

5743

FMI

9 — Abnormal update rate

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 9 tells the shop the type of failure to test for: abnormal update rate.
• Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.

Related fault codes

• PACCAR Fault Code P3872 — PM Sensor – Data Not Rational, Drifted Low
• PACCAR Fault Code P3982 — Exhaust Gas Temperature After DPF or SCR Catalyst – Data Erratic, Intermittent or Incorrect
• PACCAR Fault Code P3988 — Fuel Dosing Valve – Voltage Too High or Short Circuit to Supply
• PACCAR Fault Code P3872 — CAN Communication – Message Timeout from SCR Exhaust Gas Temperature Sensors ECU
• PACCAR Fault Code P3946 — Exhaust Gas Temperature Sensors SCR – Voltage Too High or Short Circuit to Supply
• PACCAR Fault Code P3947 — Exhaust Gas Temperature Sensors SCR – Voltage Too Low or Short Circuit to Ground
• PACCAR Fault Code P3948 — Exhaust Gas Temperature Sensors SCR – Data Valid But Too High
• PACCAR Fault Code P3949 — CAN – Time-Out from SCR Exhaust Gas Temperature Sensors ECU