| Symptoms |
Possible Causes |
Remedy |
| Coolant Leakage |
- From the thermostat gasket
|
Check the mounting bolts |
- Check the tightening torque of the mounting bolts
|
- Tighten the bolts and check for leaks again.
|
| Check the gasket for damage |
- Check the gasket or seal for damage
|
- Replace the gaskets and reuse the thermostat.
|
| Excessive cooling |
- Insufficient heater output (cold air blows out)
- Temperature gauge indicates "LOW"
|
Visually check after removing the radiator cap. |
- Insufficient coolant or leakage.
|
- After adding coolant, repeat the check.
|
| GDS Check and Engine Start |
- Check the diagnostic trouble codes
- Check the connection of the fan clutch or fan motor.
※ If the fan clutch is always engaged, noise will be heard at idle. |
- Check the engine coolant temperature sensor, wiring and connectors.
- Replace the components.
|
| Remove the thermostat and inspect. |
- Check for dust or debris in the thermostat valve.
- Check the thermostat seating.
|
- Clean the thermostat valve and reuse the thermostat.
- Replace the thermostat if it does not operate properly.
|
| Overheating |
- Engine Overheated
- Temperature gauge indicates "HI"
|
Visually check after removing the radiator cap. |
- Insufficient coolant or leakage. ※ Be careful when removing the radiator cap of an overheated vehicle.
- Check for air in the cooling system.
|
- After adding coolant, repeat the check.
- Check the cylinder head gasket for damage and the tightening torque of the mounting bolts.
|
| GDS Check and Engine Start |
- Check the diagnostic trouble codes
- Check the operation of the fan motor as the temperature changes.
- Check whether the fan clutch is slipping.
- Check the water pump for proper fit or damaged impeller.
|
- Check the engine coolant temperature sensor, wiring and connectors.
- Check the fan motor, relay and connector.
- Replace the fan clutch if it does not operate properly.
- Replace the water pump if it does not operate properly.
|
| Immerse the thermostat in boiling water and inspect it. |
- After removing the thermostat, check its operation.
※ Make sure the thermostat opens at the valve opening temperature. |
- Replace the thermostat if it does not operate properly.
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