| Cooling system parts malfunction | Poor heat transfer | Water pump malfunction | Worn or loose drive belt | — |
| Thermostat stuck closed | Coolant circulation |
| Damaged fins | Dust contamination or rock clogging |
| Mechanical damage |
| Clogged radiator cooling tube | Excess foreign material (rust, dirt, sand, etc.) |
| Reduced air flow | Cooling fan does not operate | Engine cooling fans | — |
| High resistance to fan rotation |
| Damaged fan blades |
| Damaged radiator shroud | — | Radiator shroud | — |
| Improper coolant mixture ratio | — | Coolant viscosity | — |
| Poor coolant quality | — | Periodic maintenance | — |
| Insufficient coolant | Coolant leaks | Cooling hose | Loose clamp |
| Cracked hose |
| Water pump | Poor sealing |
| Radiator cap | Loose |
| Poor sealing |
| Radiator | O-ring for damage, deterioration or improper fitting |
| Cracked radiator tank |
| Cracked radiator core |
| Reservoir tank | Cracked reservoir tank |
| Overflowing reservoir tank | Exhaust gas leaks into cooling system | Cylinder head deterioration |
| Cylinder head gasket deterioration |
| Except cooling system parts malfunction | — | Overload on engine | Abusive driving | High engine rpm under no load |
| Driving in low gear for extended time |
| Driving at extremely high speed |
| Powertrain system malfunction | — |
| Installed improper size wheels and tires |
| Dragging brakes |
| Improper ignition timing |
| Blocked or restricted air flow | Blocked radiator grille | Installed car brassiere | — |
| Mud contamination or paper clogging |
| Blocked bumper |
| Blocked radiator |
| Blocked condenser |
| Installed large fog light |