Electric Thermostat (ECT): Troubleshooting

WARNING: This page is about a different variant/trim than selected.

Symptoms		Possible Causes		Remedy
Coolant leakage	From the thermostat gasket	Check the mounting nuts	Check the torque of the mounting nuts	Retighten the bolts and check leakage again.
Coolant leakage	From the thermostat gasket	Check the gasket for damage	Check gasket or seal for damage	Replace gaskets and reuse the thermostat.
Cooled excessively	Low heater performance (cool air blows-out) Thermogauge indicates 'LOW'	Visually check after removing the radiator cap.	Insufficient coolant or leakage.	After refilling coolant, recheck.
		KDS check & Starting engine	Check DTCs Check the fan motor performance as temperature varies. Check connection of the fan clutch or the fan motor. * If the fan clutch is always connected, there will be a noise at idle.	Check the engine coolant sensor, wiring and connectors. Check the fan motor, the relay and the connector. Replace the components.
		Remove the thermostat and inspect	Check if there are dusts or chips in the thermostat valve. Check adherence of the thermostat.	Clean the thermostat valve and reuse the thermostat. Replace the thermostat, if it doesn't work properly.
Heated excessively	Engine overheated Thermogauge indicates 'HI'	Visually check after removing the radiator cap.	Insufficient coolant or leakage. * Be careful when removing a radiator cap of the overheated vehicle. Check air in cooling system.	After refilling coolant, recheck. Check the cylinder head gaskets for damage and the tightening torque of the mounting bolts.
		KDS check & Starting engine	Check DTCs Check the fan motor performance as temperature varies. Check if the fan clutch slips. Check the water pump adherence or impeller damaged.	Check the engine coolant sensor, wiring and connectors. Check the fan motor, the relay and the connector. Replace the fan clutch, if it doesn't work properly. Replace the water pump, if it doesn't work properly.
		Immerse the thermostat in boiling water and inspection.	After removing the thermostat, check it works properly. * Check the thermostat opens at the valve opening temperature.	Replace the thermostat, if it doesn't work properly.