Park on a level surface and let the engine cool completely
Check the coolant reservoir level
Inspect the radiator, hoses, clamps, and connections for wet spots or residue
Look under the vehicle for puddles or drips
Check around the water pump for signs of leakage
Inspect the radiator cap and reservoir cap for cracks or damage
Examine the heater hoses and firewall area
Look for dried coolant stains or crusty buildup
Check the engine block, thermostat housing, and freeze plugs
Use a pressure tester to pressurize the cooling system
Add UV dye to the coolant and inspect with a UV light
Watch for white smoke from the exhaust or sweet-smelling fumes
Monitor for overheating or frequent coolant loss
Have a mechanic perform a combustion gas test if the leak is not visible