FMI 17 — Data valid but below normal operating range — least severe level
Real reading, slightly low. Early warning stage.
Common causes
- Slight leak, wear or level loss
- Weak pump or regulator
- Sensor drifted low
What to test, in order
- Trend the value over a road test
- Check levels and look for slow leaks
- Compare with a companion sensor
- Test pump/regulator output against spec
Codes we document with FMI 17
SPN 94 FMI 17Fuel delivery pressure low · MackSPN 168 FMI 17Battery potential / power input low - least severe · CATSPN 168 FMI 17Battery potential / power input low - least severe · DetroitSPN 168 FMI 17Battery potential / power input low - least severe · InternationalSPN 168 FMI 17Battery potential / power input low - least severe · PACCARSPN 168 FMI 17Battery potential / power input low - least severe · MERCEDESSPN 168 FMI 17Battery potential / power input low - least severe · VolvoSPN 168 FMI 17Battery potential / power input low - least severe · MackSPN 168 FMI 17Battery potential / power input low - least severe · Cummins
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