Safe to driveTo the nearest safe stop
J1939 code SPN 657. Below — how the fault is worded at the factory by Ford Trucks, KAMAZ, MAZ and YaMZ, and what the second half of the code (FMI) means in the standard.
Ford Trucks/Ecotorq writes fault numbers in its own format: the code in the table below is a Ford code (hexadecimal, zero-padded), not a J1939 SPN. It matches the standard only where the signal itself is standard, and usually matches the title of this page by digit alone.
| FMI 19 | Tachograph (TCO) transmits faulty signal |
| FMI 3 | Cylinder 7 injector (V8): fault / warning |
| FMI 5 | Cylinder 7 injector (V8). K-line code on KamAZ-5490: MR2 15627. |
| FMI 6 | Cylinder 7 injector (V8). K-line code on KamAZ-5490: MR2 15628. |
| FMI 7 | Cylinder 7 injector (V8). K-line code on KamAZ-5490: MR2 15626. |
| FMI 8 | Cylinder 7 injector (V8): fault / warning |
| FMI 11 | Cylinder 7 injector (V8): fault / warning |
| FMI 12 | Cylinder 7 injector (V8): fault / warning. K-line code on KamAZ-5490: MR2 19644. |
| FMI 14 | Cylinder 7 injector (V8). K-line code on KamAZ-5490: MR2 19645. |
| FMI 3 | Cylinder 7 injector driver circuit fault - Negative wire shorted to battery. Blink code: 1-4-7. The engine will not start. Power will be reduced. Repair: Check the injector connectors and harness. |
| FMI 8 | Cylinder 7 injector driver circuit fault - Negative wire shorted to positive wire. Blink code: 1-4-7. The engine will not start. Power will be reduced. Repair: Check the injector connectors and harness. |
| FMI 11 | Cylinder 7 injector driver circuit fault - Depends on calibration. Blink code: 1-4-7. The engine will not start. Power will be reduced. Repair: Check the injector connectors and harness. |
| FMI 12 | Cylinder 7 injector driver circuit fault - Open circuit. Blink code: 1-4-7. Power will be reduced. Repair: Check the injector connectors and harness. |
| FMI 3 | Cylinder 7 injector driver circuit fault (Negative wire shorted to battery). Blink code: 1-4-7. The engine will not start. Power will be reduced. Repair: Check the injector connectors and harness. |
| FMI 8 | Cylinder 7 injector driver circuit fault (Negative wire shorted to positive wire). Blink code: 1-4-7. The engine will not start. Power will be reduced. Repair: Check the injector connectors and harness. |
| FMI 11 | Cylinder 7 injector driver circuit fault (Calibration dependent). Blink code: 1-4-7. The engine will not start. Power will be reduced. Repair: Check the injector connectors and harness. |
| FMI 12 | Cylinder 7 injector driver circuit fault (Open circuit). Blink code: 1-4-7. Power will be reduced. Repair: Check the injector connectors and harness. |
Safe to drive. Below — how much time you have and what happens if you keep going.
Fuel is not arriving in the right amount or at the right pressure. It shows up first on climbs and under load.
You will most likely stall out on the road, and may not restart on the shoulder. A clogged filter or water in the tank you can nurse to a shop; a failing injection pump you cannot.
This is an electrical fault: an open, a short or a bad contact in the sensor circuit. The value it measures is most likely fine. You can drive. But until the circuit is repaired this system runs blind and cannot warn you about a real failure.
Check the fuel filter and water trap, drain the water. In cold weather, suspect fuel waxing.
This code is often not the fault itself but a knock-on. If any of these is in the same readout, start with it:
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.