Hyundai Kona: Cooling System / Thermostat Troubleshooting

Troubleshooting
Symptoms
Possible Causes
Remedy
Coolant 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)
•
Temperature gauge indicates 'LOW'
Visually check after removing the radiator cap.
•
Insufficient coolant or leakage.
•
After refilling coolant, recheck.
GDS check&Starting engine
•
Check DTCs
•
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.
•
Replace the componants.
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
•
Temperature gauge 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.
GDS 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.

Thermostat Repair procedures
Removal    • Disassembly of the thermostat would have an adverse effect, causing ...

Lubrication System
...

Other information:

Hyundai Kona (OS) 2018-2026 Service Manual: Center Pillar Trim Components and components location
Component Location 1. Center pillar lower trim 2. Center pillar upper trim ...

Hyundai Kona (OS) 2018-2026 Owners Manual: Check tire pressure
You can check the tire pressure in the Assist mode on the cluster. Refer to the "LCD Display Modes" in chapter 3. Tire pressure is displayed after a few minutes of driving after initial engine start up. If tire pressure is not displayed when the vehicle is stopped, "Drive to display" mess ...

© 2018-2026 www.hkona.com