DTC P0128 - Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)

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DTC DESCRIPTION P0128 - COOLANT THERMOSTAT (COOLANT TEMPERATURE BELOW THERMOSTAT REGULATING TEMPERATURE)

Description:	This DTC sets when the thermostat monitor has not achieved the required engine operating temperature within a specified amount of time after starting the engine.
Possible Causes:	Insufficient warm up time Low engine coolant level Leaking or stuck open thermostat Damaged engine coolant temperature (ECT) sensor Damaged cylinder head temperature (CHT) sensor
Diagnostic Aids:	Refer to THERMOSTAT MONITOR for system information.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to PINPOINT TEST K .