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Home >> Infiniti >> 2021 >> Q50 Pure, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (DTCS) (1 Of 6) >> Engine (ECM) >> DTC P0128: Thermostat Function >> DTC Description >> VR30DDTT engine >> 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.

DTC

CONSULT screen terms

(Trouble diagnosis content)

DTC detection condition

P0128

THERMSTAT FNCTN

[Coolant thermostat (coolant temperature below thermostat regulating temperature)]

Diagnosis condition

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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

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