1. Low coolant level Check the engine and cooling system for external coolant leaks: Repair and replace lost coolant if necessary.
2. The radiator fins are damaged or clogged with debris: check the radiator fins. Clean and repair heat sink as necessary.
3. Collapsed, restricted or leaking cooling system hoses: Check the radiator hoses.
4. Low lubricating oil level Check the lubricating oil level: check the oil dipstick scale and the capacity of the oil pan. Fills the system to the specified level.
5. Damaged or missing fan shroud or damaged or missing air recirculation baffle: Check shroud and recirculation baffle. Repair, replace or install as necessary.
6. Loose, tight or misaligned fan drive belt: Check the fan drive belt.
7. The fan drive is faulty: check the fan drive.
8. Incorrect, faulty or low pressure radiator cap: Check the radiator pressure cap.
9. The thermometer is faulty: check and/or replace the thermometer.
10. Incorrect or malfunctioning thermostat: Check and/or replace the thermometer.
11. Fuel pump failure Check the fuel pump on the fuel pump test bench: replace the fuel pump if necessary.
12. Engine water pump failure: Check whether the engine water pump works normally. Replace the water pump if necessary.
13. Air in the cooling system: Check and drain the cooling system.
14. The cooling system is contaminated with dirt, scale or sludge: clean the cooling system.
