The electrical system of a modern automobile runs at how many volts when the engine is running?

The electrical system of a modern automobile typically operates at around 14.0 volts when the engine is running. This increase from the nominal 12.0 volts is due to the functioning of the alternator, which generates electrical power to recharge the battery and power the vehicle's electronics while the engine is on. The 14.0 volts ensure that the battery gets adequately charged and that there is enough voltage to run all the electrical systems efficiently, including lights, infotainment, and ignition systems.

The 12.0 volts measurement refers to the battery's resting voltage when the vehicle is off and not being charged. In contrast, the higher voltage during operation accounts for the required power surplus to handle various loads and support the vehicle's functionality. This system is standard in most vehicles today, which are designed around a 12-volt electrical architecture.