A method and system for diagnosing a fault that includes a decision tree having a plurality of decision points wherein at least some of the plurality of decision points terminate in a resolution point representing a diagnosis for the fault. Also included is a plurality of queries each having at least a first response and a second response where each of the plurality of queries being associated with one of the plurality of decision points. The system also includes a knowledge base that includes a plurality of first images where each of the plurality of first images illustrate one of the first responses. A user interface is included for presenting the plurality of queries and the illustrative first images to a user. The user navigates the decision tree by responding to at least some of the plurality of queries by viewing the illustrative first images and basing a selection between the first response and the second response associated with said at least some of said queries on said illustrative first images. Finally, the fault is diagnosed when the user navigates the decision tree until the resolution point is reached.