High coolant temperature
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.
SPN 110 — High coolant temperature
SPN 110 is the parameter the ECM is flagging on CAT, Volvo, PACCAR engines. The FMI that comes with it tells you how it failed. Each failure mode below has its own causes and its own test order — do not treat them as the same repair.
Coolant temperature above limit
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.
Engine coolant temperature too high
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.
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