DTC P0128: Notes

DTC P0128 (MZI-3.5) DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0128	Coolant thermostat (coolant temp below thermostat regulating temperature)
DETECTION CONDITION	P0128 Indicates that the thermostat monitor has not achieved the required engine operating temperature within a specified amount of time after starting the engine.
POSSIBLE CAUSE	Insufficient warm up time Low engine coolant level Leaking or stuck open thermostat Inoperative cylinder head temperature (CHT) sensor