Using a failure modes, effects and diagnostic analysis (FMEDA) to measure diagnostic coverage in programmable electronic systems

One of the key issues in the quantitative evaluation of programmable electronic systems is the diagnostic capability of the equipment. This is measured by a parameter called the Coverage Factor, C. This factor can vary widely. The range of possible values is often the subject of great debate. Within limits, the diagnostic coverage factor can be calculated by knowing which component failure modes are detected by diagnostics. An extension of the Failure Modes and Effects Analysis (FMEA) can be used to show this information. This extension, called a Failure Modes, Effects and Diagnostic Analysis can serve as a useful design verification tool as well as a means to provide more precise input to reliability and safety modeling.