A Static Diagnostics Engine arrives at predetermined diagnostic conclusions by performing diagnosis using a predetermined test order. This type of diagnostics is sometimes referred to as "Fault Tree Diagnostics" due to the fact that the predetermined test order and possible diagnoses can easily be represented as a flowchart-like tree. Test Requirements Documents (TRDs) have also been used to represent static diagnostic procedures. Unlike dynamic or semi-dynamic diagnostics, static diagnostics requres that all tests be performed in the predetermined order (tests cannot be skipped, postponed or inserted without compromising the validity of the diagnostic conclusions).
Because static diagnostic procedures contain a fixed number of isolation paths, they can be fully verified using a deductive approach (this is not the case for either dynamic or semi-dynamic diagnostics). The predetermined test order and diagnostic conclusions can be used to examine the diagnosis of any fault or combination of faults in the system.
Deployed static diagnostics consists of both the predetermined test order and the set of diagnostic conclusions that have been predetermined for each possible isolation path.
