The electrical wiring systems of modern aircraft are extremely complex and, therefore, very difficult to assess and repair quickly. These difficulties will only increase as more sophisticated aircraft are fielded with advanced technologies providing increased capabilities, which will increase the number of wires required. To help overcome these difficulties, a working prototype of a computerized maintenance aid has been developed under government contract for the U.S. Air Force. Field tests have shown significant reductions in diagnostic/repair times and in skill levels required to perform the work.This tool has the potential to help airlines reduce the time and cost of wiring related maintenance activities. Furthermore, this concept can be extrapolated to other systems within an aircraft (e.g., fuel, hydraulics, environmental control) as well as ships and ground vehicles, including automobiles. With the increasing complexity of automobile electrical systems, this concept could also be applicable to automobile maintenance.