Do not driveTo the nearest safe stop
SPN 4236 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 0 | Closed-loop value too high |
| FMI 1 | Closed-loop value too low |
| SPN 4236 FMI 04236/0 · 4236.0 | data above normal range (most severe level) |
| SPN 4236 FMI 14236/1 · 4236.1 | data below normal range (most severe level) |
Do not drive. Stop as soon as it’s safe to do so — don’t keep going.
The code is flagged critical: the manufacturer considers it unsafe to keep driving without checking.
This code alone cannot say what will fail next, so stop at the first safe opportunity and look at it on the spot.
That said, the manufacturer flags this code as critical — if in doubt, it is safer to stop and check on the spot.
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.