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Home >> Mitsubishi >> 2023 >> Outlander ES, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (1 Of 5) >> DTC/Circuit Diagnosis >> DTC P0128: Thermostat Function >> DTC Description >> DTC Detection Logic
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DTC Detection Logic

Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long enough.

This is due to a leak in the seal or the thermostat being stuck open.

P0128 THERMOSTAT FUNCTION - DTC DESCRIPTION

DTC M.U.T.-III SE screen terms (Trouble diagnosis content) DTC detection condition
P0128 00 THERMSTAT FNCTN
[Coolant thermostat (coolant temperature below thermostat regulating temperature)]
Diagnosis condition -
Signal (terminal) Engine coolant temperature sensor signal
Threshold The engine coolant temperature does not reach to specified temperature even though the engine has run long enough.
Diagnosis delay time -