Method for operating an electrical system of a motor vehicle, and motor vehicle

A method for operating an electrical system of a motor vehicle, the motor vehicle comprising a motor, and the electrical system comprising a first power source for providing an operating voltage for at least one part of the electrical system and at least a second power source, comprising the steps of:

• monitoring, by a control system of the motor vehicle, an electrically conductive connection of the first power source to the electrical system to detect an interruption of the electrically conductive connection;
• detecting, by the control system, at least one condition indicative of a voluntary removal of an electrical contact in the electrically conductive connection;
• detecting, by the control system, an intentional interruption of the electrically conductive connection when both the interruption of the electrically conductive connection is detected and the at least one condition is detected;
• separating, by the control system, in response to the detected intentional interruption of the electrically conductive connection, the at least one second power source of the electrical system from the electrical system;
• and
• deactivating, by the control system, in response to the detected intentional interruption of the electrically conductive connection, the at least one second power source of the electrical system.