Safe to driveDrivable, but watch it yourself
J1939 code SPN 1056. Below — how the fault is worded at the factory by Bendix ABS/ESP, Knorr-Bremse EBS, MAN and Renault Trucks, and what the second half of the code (FMI) means in the standard.
Bendix ABS/ESPKnorr-Bremse EBSMANRenault Trucks
| FMI 3 | Trailer PMV REL Solenoid Shorted to Voltage; Trailer PMV HLD Solenoid Shorted to Voltage |
| FMI 4 | Trailer PMV REL Solenoid Shorted to Ground; Trailer PMV HLD Solenoid Shorted to Ground |
| FMI 5 | Trailer PMV REL Solenoid Open Circuit; Trailer PMV HLD Solenoid Open Circuit; Trailer PMV CMN Open Circuit |
| FMI 7 | PMV Configuration Error |
| FMI 3 | Module trailer control, adjustable max pressure. Not identified |
| FMI 3 | Module trailer control adjustable maximum pressure - Not identified |
| FMI 7 | Trailer control module pneumatic fault or module internal fault. Repair: Check the air supply pressure, the minimum pressure switches and the pneumatic circuit of the trailer module. Check the parking brake. Clear the fault codes. If the fault persists, replace the trailer brake control module. |
| FMI 9 | Trailer control module internal fault, or communication failure between the additional axle module, the EBS unit and the trailer control module. Repair: Check the electrical connections between the EBS unit and the trailer control module (continuity of the 4 wires X3/3, 6, 9, 12). Check the supply of the EBS unit (positive on X1/7, X1/8 and negative on X1/10, X1/12) and of the module (X3/3 and X3/12). Check the fuses that belong to the EBS. Clear the fault codes. If the fault persists, replace the trailer control module. |
| FMI 11 | Incompatibility between the trailer control module and the EBS unit. Repair: Check the part numbers of the module and the EBS unit. |
| FMI 12 | Trailer control module internal fault. Repair: Clear the fault codes. If the fault persists, replace the trailer control module. |
| FMI 13 | Trailer control module internal fault. Repair: Perform the programming. Clear the fault codes. If the fault persists, replace the trailer control module. |
| FMI 16 | Trailer control module internal fault. Repair: Clear the fault codes. If the fault persists, replace the trailer control module. |
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.