Safe to driveDrivable, but watch it yourself
SPN 520235 is a manufacturer number outside the standard J1939 table: different makes can put different things under it. Below — how it is worded by KAMAZ and SITRAK, and what the second half of the code (FMI) means.
| FMI 3 | 12V sensor supply voltage |
| FMI 4 | 12V sensor supply voltage |
| FMI 11 | ECU monitoring module: sensor supply voltage above the upper limit. Scan tool code: P1600. Effect: OBD limits torque immediately. |
| FMI 20 | ECU monitoring module: sensor supply voltage below the lower limit. Scan tool code: P1601. Effect: OBD limits torque immediately. |
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.