What does SPN 3217 FMI 0 (3217/0) mean?

Aftertreatment 1 Intake O2: data above normal range (most severe level).

What does SPN 3217 FMI 1 (3217/1) mean?

Aftertreatment 1 Intake O2: data below normal range (most severe level).

Do not drive. Stop as soon as it’s safe to do so — don’t keep going.

Do not driveTo the nearest safe stop

J1939 code SPN 3217. Below — how the fault is worded at the factory by SITRAK, and what the second half of the code (FMI) means in the standard.

FMI 0	NOx sensor supply voltage too high. Scan tool code: P2200. Effect: Torque will be limited after 50 hours of operation.
FMI 1	NOx sensor supply voltage too high. Scan tool code: P2200. Effect: Torque will be limited after 50 hours of operation.
FMI 2	NOx sensor reading too high. Scan tool code: P2201. Effect: Torque will be limited after 50 hours of operation.
FMI 5	UEGO sensor open circuit
FMI 15	NOx sensor supply voltage too high. Scan tool code: P2200. Effect: Torque will be limited after 50 hours of operation.
FMI 16	NOx sensor supply voltage too high. Scan tool code: P2200. Effect: Torque will be limited after 50 hours of operation.
FMI 17	NOx sensor supply voltage too low. Scan tool code: P2200. Effect: Torque will be limited after 50 hours of operation.
FMI 18	NOx sensor supply voltage too low. Scan tool code: P2200. Effect: Torque will be limited after 50 hours of operation.

SPN 3217 FMI 03217/0 · 3217.0	data above normal range (most severe level)
SPN 3217 FMI 13217/1 · 3217.1	data below normal range (most severe level)
SPN 3217 FMI 23217/2 · 3217.2	data erratic or intermittent
SPN 3217 FMI 53217/5 · 3217.5	current below normal or open circuit
SPN 3217 FMI 153217/15 · 3217.15	above normal — low severity
SPN 3217 FMI 163217/16 · 3217.16	above normal — moderate severity
SPN 3217 FMI 173217/17 · 3217.17	below normal — low severity
SPN 3217 FMI 183217/18 · 3217.18	below normal — moderate severity

Do not drive. Stop as soon as it’s safe to do so — don’t keep going.

Time you have: To the nearest safe stop

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.