A gaming machine is provided having a cabinet with one or more technician accessible and normally locked compartments that include respective compartment service lights. A respective gaming power supply node is provided in at least one of the compartments where power is supplied to that node for a limited time during servicing. In order to allow for long durations of service lighting in the compartment, a service backup battery is added to the compartment. A power selecting circuit is employed to automatically select either the service backup battery or the gaming power supply node for supplying power to service lights in the compartment.