Fault

A technique to explore the many potential or actual causes of product or system failure. FTA is a top-down analysis method, where one starts with a symptom or fault and then lists the many possible causes in a structured manner. It provides a structured way to organize information about the occurrence of the top event. FTA may be useful to create a system reliability model to estimate system reliability performance or to organize brainstorming potential paths of events that lead to the occurrence of the top event.

A process to detect and remedy inadequacies in an item. Not to be confused with burn-in, fault-isolation, or screening.

The duration from the occurrence of an anomaly or event till the fault is isolated (determination a fault exists) and identified (optional — labeling the type of fault).

The hardware, software, or other documented means used to determine that a malfunction has occurred and to isolate the cause of the malfunction. Also refers to "the action of detecting and isolating failures or faults."

A fault indicated by BIT or other monitoring circuitry where no fault can be found or confirmed.