Forvia Faurecia ranked at the 7th worldwide position as automotive supplier is accelerating its digitalization for the whole life cycle of its products. Part of automotive components require heat-treatment at high temperature under controlled atmosphere and regulated thermochemical reactions. Besides high amount of energy, high temperature and cycle times are involved in the context of fluctuating production. Most of process parameters are monitored, but nowadays evolution of information technology enables to escalate monitoring of process parameters to a new level thanks to a large range of sensors capable of communicating with each other. The present heat-treatment process has been re-modelled by taking opportunities to connect those sensors for a full digitalization. The purpose is to show how the new connected architecture can improve the heat-treatment process, extend the functionalities of each existing tool and impact positively on cost, CO2 emission, quality, and process efficiency. From the current infrastructure to the new, comparative tables are given to quantify cost, energy, and CO2 emission saving.