The block heater cord on a 2003 Chevy Cavalier, if it has one (not all models did), is typically located
in the front of the engine compartment, near the driver's side. It will be a heavy-duty cord plugged into the engine block itself. Look for a cord that's thicker and more durable than other wires in the engine bay. It might be tucked away, possibly near the lower radiator hose or behind other components.
Because the location can vary slightly depending on the specific engine and any aftermarket modifications, a thorough visual inspection of the entire engine bay's front, particularly the driver's side, is necessary to locate it.
