Generator shuts down and displays E05 after running for a short period under load.

Safety first: Turn the generator OFF and allow it to cool completely before opening the enclosure or radiator cap. Hot coolant can cause severe burns.

• Check coolant level: On liquid-cooled Hyundai Power standby generators, inspect the coolant reservoir and radiator (when cool). Top up with the specified coolant mixture if low. Investigate for leaks at hoses, water pump, and radiator.
• Inspect airflow: Ensure that the generator enclosure vents are not blocked by debris, snow, or vegetation. Clean any dust and dirt from the radiator fins or engine shrouds using low-pressure air.
• Verify fan operation: Start the generator and observe whether the electric radiator fan (or engine-driven fan) operates when the engine warms up. Check the fan fuse, relay, and wiring. Replace a failed Hyundai Power cooling fan assembly or fan belt as needed.
• Check coolant temperature sensor: Inspect the sensor connector for corrosion. If the generator overheats according to the controller but the engine is not actually hot, the sensor may be faulty and should be tested or replaced.
• Load check: Confirm that the generator is not overloaded beyond its rated kW. Excessive load can cause overheating. Reduce non-essential loads and retest.