Serial communication verification and safety control is disclosed. A multi-part system such as a battery management system can include distributed or subsidiary components for determining status of various parts of the system with the components in serial or point-to-point communication with a collective main controller. A safety controller can be implemented to passively be coupled to the serial or point-to-point communication between the main controller and the subsidiary units. The safety controller can monitor and verify the communication between the main controller and the subsidiary units and send a safety command or verification indicator in another line of communication separate from the communication bus between the main controller and the subsidiary units.