Do not driveMinutes
J1939 code SPN 1086. Below — how the fault is worded at the factory by Ford Trucks and KAMAZ, 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 9 | Driveline CAN wiring defective, terminating resistor of driveline CAN bus defective, error in engine control unit (EDC) |
| FMI 4 | Air pressure sensor circuit, circuit 3, shorted to ground |
| FMI 5 | Air pressure sensor circuit, circuit 3, open |
| FMI 7 | Air pressure sensor signal, circuit 3, out of range |
Do not drive. Stop as soon as it’s safe to do so — don’t keep going.
Part of the brake circuit or ABS/EBS is out of service. The pedal may still feel normal — until the first emergency stop or descent.
Next comes longer stopping distance, a skid on a slick surface, failure on a long downgrade. This is the case where "I will take it slow" does not work.
Let the air system build to working pressure and listen for leaks. Don’t drive with faulty brakes.
If the value really did go out of range, rather than a sensor circuit being broken, these normally light up after it:
They are not fixed separately — they go out together with this one. The list is deliberately short: only the links the reference is sure about.
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.