Generator shuts down, controller shows E-11, coolant level normal

Safety: Never open the cooling system when hot. Disable automatic start and allow the engine to cool completely.

• Check coolant level: Inspect the expansion tank and radiator (if accessible) and top up with CAT-approved coolant if low. Note how much coolant is added.
• Inspect for leaks: Look for dried coolant residue or wet spots around hoses, clamps, radiator core, water pump, and engine block. Tighten loose clamps and replace cracked hoses.
• Radiator cap: Inspect the radiator or tank cap seal. Replace if the seal is cracked or the spring is weak.
• Coolant level sensor: Locate the sensor in the tank or radiator. Check connector and wiring for corrosion or damage. Clean contacts and reseat.
• Clear code and monitor: Clear E-11 and run the generator while monitoring coolant level over several hours of operation.

Repeated coolant loss or persistent E-11 with no visible leaks suggests internal leaks or sensor/controller issues that require professional diagnosis.