Q: How to Check and Replace the Engine-Mounted Cooling Fan and radiator-mounted cooling fan?
A: The engine-mounted cooling fan, also known as the viscous fan, is controlled by the PCM and should be checked by a qualified repair shop if it is not coming on and causing the engine to overheat. Symptoms of fan clutch failure include noisy operation, looseness, vibration, and fluid leakage. To check the fan, rock it back and forth for excessive bearing play and turn the blades by hand. For a hot engine check, start the engine and let it warm up, then turn off the engine and try turning the fan by hand. For a radiator-mounted electric cooling fan, if it is not coming on, the fan motor can be tested by connecting it directly to the battery. For component replacement, the viscous and electric cooling fans are removed together. For diesel engines, the process is similar, but there may be additional steps. For 2010 and later models, the process involves disconnecting the battery, removing the radiator top cover plate, detaching the viscous fan, and unclipping the fan shrouds.