Safe to driveUntil the next service
J1939 code SPN 612. Below — how the fault is worded at the factory by DAF, Dongfeng and SITRAK, and what the second half of the code (FMI) means in the standard.
| FMI 2 | Engine speed and position signals both missing/implausible |
| FMI 2 | Signals from both engine speed sensors not detected |
| FMI 19 | NH3 sensor short circuit to battery. Scan tool code: P24E8. Effect: Torque may be limited. |
| SPN 612 FMI 2612/2 · 612.2 | data erratic or intermittent |
| SPN 612 FMI 19612/19 · 612.19 | error in received network data |
Safe to drive. Below — how much time you have and what happens if you keep going.
A standalone fault with no immediate consequences for driving.
Show the codes at the next service. If a second code from the same system appears, stop putting it off.
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.