FMI 0 — Data valid but above normal operating range — most severe level
The sensor is working and the reading is real, but the value is dangerously high. This is the engine telling you it has a mechanical or system problem, not a wiring problem.
Common causes
- Actual overheat, overpressure or overspeed condition
- Restricted cooling, airflow or exhaust path
- Failed control device holding the system high
- Sensor reading high because it is contaminated or drifted
What to test, in order
- Read live data and compare the suspect value against a second sensor or a mechanical gauge
- Verify the physical condition first — coolant level, airflow, restriction, oil level
- Only after the mechanical side checks out, test the sensor against a known-good reference
- Check for derate or shutdown history in the ECM
Codes we document with FMI 0
SPN 105 FMI 0Intake manifold air temperature high · CATSPN 105 FMI 0Intake manifold air temperature above normal - most severe · DetroitSPN 105 FMI 0Intake manifold air temperature above normal - most severe · InternationalSPN 105 FMI 0Intake manifold air temperature above normal - most severe · PACCARSPN 105 FMI 0Intake manifold air temperature above normal - most severe · MERCEDESSPN 105 FMI 0Intake manifold air temperature above normal - most severe · VolvoSPN 105 FMI 0Intake manifold air temperature above normal - most severe · MackSPN 105 FMI 0Intake manifold air temperature above normal - most severe · CumminsSPN 110 FMI 0Engine coolant temperature too high · PACCARSPN 110 FMI 0Coolant temperature above limit · VolvoSPN 110 FMI 0High coolant temperature · CATSPN 110 FMI 0Engine coolant temperature above normal - most severe · DetroitSPN 110 FMI 0Engine coolant temperature above normal - most severe · InternationalSPN 110 FMI 0Engine coolant temperature above normal - most severe · MERCEDESSPN 110 FMI 0Engine coolant temperature above normal - most severe · MackSPN 110 FMI 0Engine coolant temperature above normal - most severe · CumminsSPN 177 FMI 0Transmission oil temperature too high · All makesSPN 190 FMI 0Engine overspeed · MackSPN 190 FMI 0Engine speed above normal - most severe · CATSPN 190 FMI 0Engine speed above normal - most severe · DetroitSPN 190 FMI 0Engine speed above normal - most severe · InternationalSPN 190 FMI 0Engine speed above normal - most severe · PACCARSPN 190 FMI 0Engine speed above normal - most severe · MERCEDESSPN 190 FMI 0Engine speed above normal - most severe · Volvo
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