Hyundai Sonata: Thermostat. Troubleshooting - Cooling System - Engine Mechanical SystemHyundai Sonata: 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 blows-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 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 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
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.
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 and Installation Disassembly of the thermostat would have an adverse effect, causing a lowering of cooling efficiency. ...

    See also:

    Armed stage
    Using the smart key Park the vehicle and stop the engine. Arm the system as described below. 1.Turn off the engine. 2.Make sure that all doors, the engine hood and trunk lid are closed and latched. ...

    Drive Belt Tensioner Repair procedures
    Removal and Installation 1. Remove the drive belt. (Refer to Timing System - "Dreve Belt") 2. Remove the alternator. (Refer to Engine Electrical System - "Alternator") 3. Remove the alte ...

    Manifold Absolute Pressure Sensor (MAPS) Repair procedures
    Inspection 1. Connect the GDS on the Data Link Connector (DLC). 2. Measure the output voltage of the MAPS at idle and IG ON. Specification: Refer to "Specification" Removal 1. Tur ...