A vehicle has an internal combustion engine, an automatic transmission with an electrohydraulic transmission control unit, a transmission oil pump driven by the engine, and an electronic engine start and stop system. The start and stop systems switches off the internal combustion engine in operating phases, in which the vehicle is temporarily stopped, if predefined operating parameters are present, and starts the internal combustion engine if a restart signal is present. A purely mechanical pressure accumulator device provides stored hydraulic pressure to the electrohydraulic transmission control unit in a time period following the starting of the internal combustion engine, in which time period, the transmission oil pump is still building-up pressure.