Coolant leakage

Leakage from the thermostat gasket

Check the mounting bolts

Check the torque of the mounting bolts.

Retighten the bolts and check leakage again.

Check the gasket for damage

Check gasket or seal for damage.

Replace gaskets and reuse the thermostat.

Cooled excessively

• Low heater performance (cool air blowed-out)

• Thermogauge indicates 'LOW'

Visually check after removing the radiator cap.

Insufficient coolant or leakage.

After refilling coolant, recheck.

GDS check＆Starting engine

Check DTCs.

Check the engine coolant sensor, wiring and connectors.

Check the fan motor performance as temperature varies.

Check the fan motor, the relay and the connector.

Check connection of the fan clutch. (If equipped)

Replace the fan clutch. (If equipped)

Remove the thermostat and inspect

Check if there are dusts or chips in the thermostat valve.

Clean the thermostat valve and reuse the thermostat.

Check adherence of 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.

After refilling coolant, recheck.

Check air in cooling system.

Check the cylinder head gaskets for damage and the tightening torque of the mounting bolts.

GDS check＆Starting engine

Check DTCs.

Check the engine coolant sensor, wiring and connectors.

Check the fan motor performance as temperature varies.

Check the fan motor, the relay and the connector.

Check if the fan clutch slips. (If equipped)

Replace the fan clutch. (If equipped)

Check the water pump adherence or impeller damaged.

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.

Replace the thermostat, if it doesn't work properly.