A diagnostic system for electronic gaming machines (EGMs) includes a power supply, and a diagnostic device in electrical connection with the power supply, the diagnostic device configured for placement within a cabinet of an EGM. The diagnostic device includes an attachment device configured to couple the diagnostic device to the EGM, a sensor array including at least one sensor for sensing a condition associated with the EGM and configured to generate conditions data based on the sensed condition, a communications device configured to transmit the conditions data to a remote location, a memory configured to store the conditions data, and a processor configured to analyze the conditions data and determine a diagnostic evaluation based upon the analyzed conditions data.