Safe to driveDrivable, but watch it yourself
J1939 code SPN 1624. Below — how the fault is worded at the factory by KAMAZ, MAZ, Mercedes-Benz, Renault Trucks, SITRAK and YaMZ, and what the second half of the code (FMI) means in the standard.
KAMAZMAZMercedes-BenzRenault TrucksSITRAKYaMZ
| FMI 3 | Vehicle speed measurement, path 2 (via CAN) |
| FMI 4 | Vehicle speed measurement, path 2 (via CAN) |
| FMI 12 | Vehicle speed measurement, path 2 (via CAN) |
| FMI 255 | Vehicle speed measurement, path 2 (via CAN) |
| FMI 2 | Vehicle speed sensor fault - Signal invalid. Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
| FMI 3 | Vehicle speed sensor fault - Voltage above allowed. Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
| FMI 4 | Vehicle speed sensor fault - Voltage below allowed. Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
| FMI 12 | Vehicle speed sensor fault - CAN bus signal implausible. Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
| FMI 9 | J1939 TCO1 Message is missing or not available |
| FMI 13 | J1939 Tachograph Vehicle Speed Signal is missing |
| FMI 9 | CAN bus link to the tachograph. Repair: Check the continuity of the CAN bus wiring connected to the EBS unit (X1/1, X1/3). Check that the tachograph is connected correctly and works. |
| FMI 18 | The speed sensor sends data that the VECU processor considers incoherent. Repair: Check the speed sensor connections. |
| FMI 3 | Tachograph vehicle speed signal above the upper limit. Scan tool code: P2158. Effect: Torque may be limited. |
| FMI 4 | Tachograph vehicle speed signal below the lower limit. Scan tool code: P2160. Effect: Torque may be limited. |
| FMI 8 | Tachograph vehicle speed signal error. Scan tool code: P2161. Effect: Torque may be limited. |
| FMI 2 | Vehicle speed sensor fault (Signal incorrect). Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
| FMI 3 | Vehicle speed sensor fault (Voltage above allowable limit). Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
| FMI 4 | Vehicle speed sensor fault (Voltage below allowable limit). Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
| FMI 12 | Vehicle speed sensor fault (Signal incorrect). Blink code: 3-2-4. Repair: Check the vehicle speed sensor and its wiring. Check the CAN bus connection. |
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.