Safe to driveDrivable, but watch it yourself
SPN 4080 is a manufacturer number outside the standard J1939 table: different makes can put different things under it. Below — how it is worded by Knorr-Bremse EBS and MAN, and what the second half of the code (FMI) means.
| FMI 6 | Module trailer management, backup valve. Short to power supply Ubat |
| FMI 7 | Module trailer management, backup valve. Short |
| FMI 9 | Module trailer management, backup valve. Faulty devices |
| FMI 10 | Module trailer management, backup valve. Open |
| FMI 6 | Module trailer management backup valve - Short to power supply |
| FMI 7 | Module trailer management backup valve - Short |
| FMI 9 | Module trailer management backup valve - Faulty |
| FMI 10 | Module trailer management backup valve - Open |
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.