Smart grid (SG) has been designed as a response to the limitations of traditional power grids caused by growing power supply demands. SG is considered a critical infrastructure in which dependability plays a crucial role and manifestation of failures can lead to severe consequences. Architecture-wise, SGs can be decomposed in several layers comprising variety of physical, software, communication and business components, each representing a potential point of failure determined by their underlying faults. In this paper, we present a systematic literature review surveying 30 different faults and failures which can occur in the SG infrastructure. The discovered faults and failures are investigated to extract details about their causes, impacts, detection techniques and counter-measures. Based on the collected information, the faults and failures are classified and mapped to Smart Grid Reference Architecture Model (SGAM), providing a useful frame of reference for practitioners and researchers dealing with hardware and software dependability in this complex domain.