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
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