This part of ISO 26021 defines the deployment process, the system architecture, CAN-based communication methods and system preconditions which have to be implemented to fulfil the use cases defined in ISO 26021-1. Additionally, the relationship to and use with other existing standards are defined. This part of ISO 26021 also describes the technical details of the on-board deployment method. The way in which the pyrotechnic devices contained in the vehicle function in conjunction with the PDT is the primary focus of this document. Under the provisions of this document, the design of the PDT or PCU can be implemented in accordance with specific functionality and hardware requirements. This part of ISO 26021 specifies the access to the PCU. This includes communication as well as the logic sequences which are involved during the activation process.