Detailed guide for SPN 110 FMI 3
Back to top ↑What SPN 110 FMI 3 means
SPN 110 identifies engine coolant outlet temperature.
FMI 3 indicates that the sensor circuit voltage is above the normal operating range or shorted toward a high source.
This is not an intake-air-temperature fault.
What you may notice
The check-engine or malfunction indicator lamp may illuminate.
The coolant-temperature value shown by diagnostic software may be unrealistic or unavailable.
What to check first
Inspect the engine coolant outlet temperature sensor connector for corrosion, bent terminals or loose connections.
Check the wiring for a short to power or an open ground circuit.
Compare coolant temperature with other temperature sensors when the engine is cold. Large differences can help identify a sensor or circuit fault.
Important
Do not diagnose an overheating condition solely from an FMI 3 electrical fault. Verify the sensor circuit and actual engine temperature before replacing cooling-system components.
Mechanic community notes for SPN 110 FMI 3
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