Safe to driveUntil the next service
SPN 4490 is a manufacturer number outside the standard J1939 table: different makes can put different things under it. Below — how it is worded by SITRAK, and what the second half of the code (FMI) means.
| FMI 18 | Loss of communication with emissions sensor |
| SPN 4490 FMI 184490/18 · 4490.18 | below normal — moderate severity |
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.