Safe to driveDrivable, but watch it yourself
J1939 code SPN 1858. Below — how the fault is worded at the factory by Renault Trucks, and what the second half of the code (FMI) means in the standard.
| FMI 3 | Wiper interval relay, short to positive. Repair: Check the continuity and insulation of the wiring with respect to +24 V (SL2/11). |
| FMI 4 | Wiper interval relay, open circuit or short to ground. Repair: Check the continuity and insulation of the wiring with respect to ground (SL2/11) |
| SPN 1858 FMI 31858/3 · 1858.3 | voltage above normal or shorted high |
| SPN 1858 FMI 41858/4 · 1858.4 | voltage below normal or shorted to ground |
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.