See also:

Checking Engine Cooling Fan
The engine cooling fan should come on automatically if the engine coolant temperature is high. ...

Check battery and cables
Winter puts additional burdens on the battery system. Visually inspect the battery and cables as described in section 7. The level of charge in your battery can be checked by an authorized HYUNDAI ...

40 MPG POWERTRAIN
Under the hood, the Hyundai Elantra is powered by an all-new 1.8-liter Nu four-cylinder engine with 148 horsepower and 131 lb-ft of torque (145 horsepower and 130 lb-ft of torque for Elantra PZEV) ...