With the development of the miniaturization of electronic systems, heat dissipation from components has become an increasing challenge. Structural electronics represent a new approach to this problem. Instead of downsizing all the elements, in this idea, electronic parts of the device are embedded into its mechanical construction. This approach has many advantages, but the reliability of systems constructed this way has not been extensively studied so far. In this work, circuits consisting of silver ink conductive traces were printed on FDM polymer substrates, with or without 0 Ω resistors, and were subjected to accelerated aging testing. The samples were divided into three groups, and for each of them, the mean time to failure was calculated, which for the best group was 8000 h. This paper also presents the mechanism that led to the failure of these systems, as well as actions that will lead to the elimination of this phenomenon.