P-Diagram is a tool that helps in developing a new product that has in-service robust performance. It considers the valid inputs from the customer (Product-KCs) based on products functionality. P-Diagram also takes into account the noise factors & control factors that may/will affect the product performance. Based on these inputs the Response (Output) of the system is analyzed. Errors states i.e. undesired response such as effect of external conditions, part-to-part variation, customer usage etc. are studied as well from the P-Diagram.
P-Diagram's response(output) can be a valid input to FMEA.