International (Navistar)
J1939 SPN/FMI
SPN 729 / FMI 5
International Fault Code SPN 729 FMI 5: IAHC Open Load / Circuit
SPN 729 FMI 5 on International / Navistar trucks means: IAHC Open Load / Circuit. The failure mode (FMI 5) is “current below normal or open circuit”.
Code details
- Manufacturer
- International (Navistar)
- Applies to
- International MaxxForce DT (2010–2019)
- Fault code
- SPN 729 FMI 5
- J1939 SPN
- 729
- FMI
- 5 — Current below normal or open circuit
- 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 5 tells the shop the type of failure to test for: current below normal or open circuit.
- 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 729 FMI 18 — IAH Monitor Fault – Lack of Heat in the Intake Manifold
- International Fault Code SPN 729 FMI 3 — IAHC Short to PWR
- International Fault Code SPN 729 FMI 4 — IAHC Short to GND
- PACCAR Fault Code P0541 — Grid Heater Relay – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (C72) or Pin (C49)
- PACCAR Fault Code P0542 — Grid Heater Relay – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (C72) or Pin (C49)
- PACCAR Fault Code P0543 — Grid Heater Relay – Current Too Low or Open Circuit on ECU (D420) Pin (C72) or Pin (C49)
- PACCAR Fault Code P0640 — Grid Heater Relay – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (C55)
- PACCAR Fault Code P1051 — Grid Heater – Data Erratic, Intermittent, or Incorrect
Source: International MaxxForce DT 2010–2019 fault code list (Diesel Laptops). See also OBD-II codes.