Designing and using cyber-physical systems integrating humans put ethics at stakes. Meanwhile, even if works are done to assess the life-cycle of these systems and the technologies used to develop them, ensuring the ethics of cyber-physical and human systems remains insufficiently studied. The objective of this paper is to suggest a guideline to ensure ethics of such systems. A case study is proposed to illustrate the guideline. This guideline is at its first step of development and needs several improvements to gain maturity and applicability.