Aim of the BMBF funded research project “ProTeck” was the manufacture of electrochromic (EC) panes for automotive applications by back-injection moulding multilayer EC systems. A plastic substrate (consisting of polycarbonate, PC) is used as the basis of these systems, ITO as the conducting layer, TiO2 as the counter electrode, PEDOT:PSS as the electrochromic layer and a PU electrolyte to join both halves. To integrate the pre-manufactured electrochromic systems in three-dimensional plastic-based parts, e.g. for automotive applications, they are back-injection moulded with amorphous plastics like PC or PMMA. Eventhough the EC pane is cooled by the cold mould wall on the one side, on the other side the hot melt (T>200°C) inserts a big amount of thermal energy into the pane. Additionally the melt induces mechanical forces to the device, particularly shearing. Both influences, together with special properties of the EC devices and their single layers, can lead to different, partly interacting effects and the destruction of the device. Effects can be e.g. worse thermal conductivity due to the metal layers, vaporising of volatile components of the electrolyte and delamination of the device. For the experiments a specialised mould was designed, to achieve a homogenous temperature and pressure profile and a reduced shear loading of the EC system. The mould allowed the production of an application-oriented demonstrator, the size of a small side window, without over-moulding the contacts. The mentioned problems could largely be solved by adjustments of the mould, the process (e.g. mould and melt temperatures, injection pressure) or the EC system (e.g. electrolyte formulation for less humidity and gas content, better adhesion). The presentation will give summary of the experiments, mentioned phenomena and appropriate measures.