Generator shuts down during run; controller displays E04 High Engine Temperature.

Safety first: Allow the engine to cool completely before opening the radiator cap. Hot coolant can cause severe burns.

• Check coolant level: Inspect the radiator and overflow bottle on the Aksa set. Top up with the specified coolant mixture if low. Investigate for leaks at hoses, water pump, and radiator.
• Inspect fan and belt: Verify the radiator fan spins freely and the belt has proper tension and is not cracked or glazed. Replace a worn or broken belt.
• Clean radiator fins: From outside the enclosure, blow compressed air through the radiator fins opposite normal airflow. Remove debris, dust, or plastic bags blocking airflow.
• Check coolant temperature sensor: Locate the sensor on the thermostat housing or cylinder head. Inspect the connector for corrosion. If the sensor reading on the controller is unrealistic (very high when cold), replace the sensor.
• Verify coolant circulation: With the engine running (if safe), feel the upper and lower radiator hoses; both should warm up. If not, the thermostat or water pump may be faulty and require professional service.