how to fix P0128 coolant thermostat code in Genesis G70 IG (2017-2023)?

Learn how to diagnose and fix P0128 coolant thermostat code in Genesis G70. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical issues.

2. Replace Thermostat

1. Drain Coolant

   • Place a drain pan under the radiator.
   • Open the radiator drain valve and allow the coolant to drain completely.

2. Remove Thermostat Housing

   • Locate the thermostat housing (typically near the engine block).
   • Remove the bolts securing the thermostat housing using a socket set.
   • Carefully detach the housing from the engine.

3. Remove Old Thermostat

   • Take out the old thermostat from the housing.
   • Clean any residual gasket material from the housing and engine surface.

4. Install New Thermostat

   • Place the new thermostat in the housing ensuring it is seated correctly.
   • Apply a new gasket or sealant as required by the manufacturer.

5. Reattach Thermostat Housing

   • Position the thermostat housing back on the engine.
   • Torque the bolts to the manufacturer's specifications (typically around 15-20 ft-lbs).

6. Refill Coolant

   • Close the radiator drain valve.
   • Refill the cooling system with the recommended coolant type.
   • Bleed the cooling system of air by running the engine with the radiator cap off until the thermostat opens.

3. Reconnect Battery

• Reconnect the negative battery terminal.