FMI 12 — Bad intelligent device or component
A smart component reported its own internal failure. The device told the ECM it is bad.
Common causes
- Internal electronics failure in a smart sensor or module
- Corrupt internal calibration
- Power supply out of range to the device
- Water intrusion
What to test, in order
- Verify supply voltage and ground quality at the device
- Check for a firmware/calibration update for that device
- Cycle power and see whether the fault self-reports again
- Replace the device when supply and network check out
Codes we document with FMI 12
SPN 629 FMI 12Engine controller internal fault · All makesSPN 629 FMI 12Engine control module internal fault · CATSPN 629 FMI 12Engine control module internal fault · DetroitSPN 629 FMI 12Engine control module internal fault · InternationalSPN 629 FMI 12Engine control module internal fault · PACCARSPN 629 FMI 12Engine control module internal fault · MERCEDESSPN 629 FMI 12Engine control module internal fault · VolvoSPN 629 FMI 12Engine control module internal fault · MackSPN 629 FMI 12Engine control module internal fault · Cummins
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