Safe to driveDrivable, but watch it yourself
J1939 code SPN 1584. Below — how the fault is worded at the factory by Ford Trucks, 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 4 | DPM Output Fuel Pressure Sensor – Constant Value Reading. FODP code (scan tool): P20DE-05. |
| FMI 5 | DPM Input Fuel Pressure Sensor – Constant Value Reading. FODP code (scan tool): P20E1-00. |
| SPN 1584 FMI 41584/4 · 1584.4 | voltage below normal or shorted to ground |
| SPN 1584 FMI 51584/5 · 1584.5 | current below normal or open circuit |
Safe to drive. Below — how much time you have and what happens if you keep going.
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.
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.