[speeder]

Pretty much all diesel vehicles sold are equipped with engine block heaters with cords unless they were sold in Arizona or some other really warm climate. And even those ones are equipped with the plug in the engine block, all that is needed is the cord to have a working heater. They all have the heater, in my experience.

They are meant to help the engine start in bitter cold weather, not 20 or 30 degrees above zero where they would be unnecessary if the battery and engine was in good condition.