Warning: The engine cooling fan turns on and off depending on the air temperature and can sometimes turn on even when the engine is not running. When doing any work near the fan blades, take extreme care to avoid injury from the running fan. The fan will turn off as soon as the coolant temperature drops - this is normal.
Checking the electric fan of the engine cooling system
The electric fan of the engine cooling system should automatically turn on when the coolant temperature is high.
Checking the air conditioner condenser fan
The air conditioner condenser fan should turn on automatically when the air conditioner is turned on.