International Fault Code SPN 3556 FMI 7: AFT Fuel Injector – Not Responding as Expected

Code details

Manufacturer

International (Navistar)

Applies to

International MaxxForce DT (2010–2019)

Fault code

SPN 3556 FMI 7

J1939 SPN

3556

FMI

7 — Mechanical system not responding or out of adjustment

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 7 tells the shop the type of failure to test for: mechanical system not responding or out of adjustment.
• 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 3556 FMI 0 — AFT Fuel Pressure 2 – Excessively High
• International Fault Code SPN 3556 FMI 1 — AFT Fuel Pressure 2 – Below Desired
• PACCAR Fault Code P3787 — Fuel Dosing Module – Used Up All Compensation
• PACCAR Fault Code P3833 — Fuel Dosing Valve – Current Too Low or Open Circuit on ECU (D442) Pin (48) or Pin (32)
• PACCAR Fault Code P3836 — Fuel Dosing Valve – Leakage Detected
• PACCAR Fault Code P3833 — Fuel Dosing Valve – Current Too Low or Open Circuit on ECU (D374) Pin (A05) or Pin (A29)