SPN 110 FMI 0 — Engine Coolant Temperature — Too High
What it means: Engine coolant temperature is above the high limit.
How serious / can you keep driving: Serious. Stop as soon as it's safe.
Check first: Reduce load and get to a safe stop; idling briefly can help, but don't keep climbing a grade hot.
Don't risk it — look up listed providers near you and give them this SPN/FMI when you call.
Listed providers nearest Macon, GA
Closest first. Tell them SPN 110 FMI 0 and what the truck is doing. RoadService.app lists these providers and does not employ them or carry out the repair.
- 0.0 mi away — based in Macon, GA · (478) 538-3245
- 0.0 mi away — based in Macon, GA · (478) 216-8330
- 0.0 mi away — based in Macon, GA · (706) 536-3376
What SPN 110 FMI 0 means
Engine coolant temperature is above the high limit. Sustained overheating warps heads and damages the engine, so the ECM warns and will derate; treat it as stop-now once confirmed on the gauge.
How serious is it?
Serious. Stop as soon as it's safe.
Most likely causes
- Low coolant level or a leak (hose, radiator, water pump, EGR cooler)
- Stuck thermostat or failed water pump
- Plugged radiator/CAC fins, debris, or a failed cooling fan/clutch
- Coolant-temp sensor fault reading high (verify before assuming)
First moves (roadside)
- Reduce load and get to a safe stop; idling briefly can help, but don't keep climbing a grade hot.
- Once cooled, check coolant level (NEVER open a hot pressurized cap) and look for leaks/steam.
- Inspect the fan engagement and the radiator/CAC face for bugs, mud, or debris blocking airflow.
- Compare gauge to actual — a sensor fault can read high, but confirm before continuing.
Common misdiagnoses
- Adding coolant and driving on without finding the leak or stuck thermostat.
- Blaming the sensor while the fan clutch isn't engaging.
- Overlooking a packed radiator/charge-air-cooler face as the airflow restriction.
FAQ
Engine coolant temperature is above the high limit. Sustained overheating warps heads and damages the engine, so the ECM warns and will derate; treat it as stop-now once confirmed on the gauge.
Serious — Stop as soon as it's safe.
The most common cause is: Low coolant level or a leak (hose, radiator, water pump, EGR cooler). Other possibilities include Stuck thermostat or failed water pump; Plugged radiator/CAC fins, debris, or a failed cooling fan/clutch; Coolant-temp sensor fault reading high (verify before assuming).
Stop as soon as it's safe. When in doubt, get a qualified mobile diesel tech on the truck before continuing.
Related codes
Codes that commonly appear alongside SPN 110 FMI 0, or share the same subsystem.
- Coolant temp sensor — voltage high (SPN 110 FMI 3)
- Coolant temp sensor — voltage low (SPN 110 FMI 4)
- Coolant temperature — moderately high (SPN 110 FMI 16)
- Coolant level — low (SPN 111 FMI 1)
- Engine Coolant Over-Temperature Condition (P0217)
- Coolant Thermostat Below Regulating Temperature (P0128)
- Fan 1 Control Circuit Malfunction (P0480)
- Fan 2 Control Circuit Malfunction (P0481)
Same symptom: Running hot
Other codes that show up as coolant temperature climbing or a hot-engine lamp.
- Engine Coolant Temperature Sensor 1 Circuit (P0115) · Cooling
- Engine Coolant Temperature Sensor Range (P0116) · Cooling
- Engine Coolant Temperature Sensor Circuit Low (P0117) · Cooling
- Engine Coolant Temperature Sensor Circuit High (P0118) · Cooling
- Engine Coolant Temperature Sensor Intermittent (P0119) · Cooling
- Fan drive — voltage high (SPN 647 FMI 3) · Engine
Find a mechanic or related guides
General diagnostic guidance for heavy-duty diesel engines (Cummins, Detroit, PACCAR, Volvo, Mack). Not a substitute for a scan-tool diagnosis on your specific truck.