A method of controlling a mild hybrid electric vehicle

A method is disclosed for controlling the operation of a mild hybrid electric vehicle 5 having an engine 10 and high and low voltage power systems selectively connectable via a DC to DC converter 14. The method comprises whenever possible using only a low voltage battery 16 forming part of the low voltage power system to power low voltage loads 17 during an engine E-stop performed automatically to save fuel and reduce emissions and whenever possible using only a high voltage battery 13 forming part of the high voltage power system to recharge the low voltage battery 16 when the engine 10 is restarted following the E-stop.