Detailed guide for SPN 412 FMI 15
Back to top ↑What SPN 412 FMI 15 means
SPN 412 FMI 15 is documented by Detroit as EGR valve temperature above the normal operating range at the least severe level.
On the documented GHG17 application, the fault sets when internal EGR valve temperature exceeds the calibrated threshold.
What you may notice
The malfunction indicator lamp and check-engine light may illuminate.
Detroit documentation lists no direct engine reaction for the documented application, although related EGR or cooling-system faults may affect drivability.
What to check first
Check for other active faults involving high engine coolant temperature or the EGR system.
Those related faults should be diagnosed first.
Verify engine operating temperature and inspect the EGR system for conditions that could cause excessive valve temperature.
Important
Do not replace the EGR valve solely from the SPN/FMI without checking companion faults.
Use the OEM troubleshooting procedure for the specific engine and emissions generation.
Mechanic community notes for SPN 412 FMI 15
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