Safe to driveDrivable, but watch it yourself
SPN 520505 is a manufacturer number outside the standard J1939 table: different makes can put different things under it. Below — how it is worded by International, Meritor (ex-WABCO) and SITRAK, and what the second half of the code (FMI) means.
InternationalMeritor (ex-WABCO)SITRAK
| FMI 6 | RPM 4 Channel 1 Overcurrent |
| FMI 14 | RPM 4 Channel 1 Overcurrent — RPM 4 Channel 1 Analog Input Data Unavailable |
| FMI 19 | RPM 4 Channel 1 Overcurrent — RPM 4 Channel 1 Analog Input Invalid Data |
| FMI 7 | Wheel Speed Permanent Slip Failure at Axle 3 Left |
| FMI 9 | Wheel Speed Jump Down Detection at Axle 3 Left |
| FMI 13 | Impermissable Tire Size Detected at Axle 3 Left |
| FMI 14 | Impermissable Deviation of Tire Size Detected at Axle 3 Left |
| FMI 12 | Deviation from the dosing quantity detected during the test injection. Scan tool code: P20FE. Effect: Torque limited, MIL on, power may drop to 60%. |
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.