11. The system of claim 9 , wherein the processor is to: receive one or more vehicle specific system fault codes and one or more vehicle specific component fault codes; determine one or more high probability failure modes based on the causal probabilities, wherein to determine, using the graphical model, one or more causal probabilities the processor is to determine conditional probabilities based on the vehicle specific system fault codes, the vehicle specific component fault codes and the graphical model; and output high probability failure modes to a user.
9. A system comprising: a memory; and a processor to: receive system fault codes, component fault codes, and failure modes; generate a first level model comprising first level causal relationships and first level causal weights between the system fault codes and the component fault codes; generate a second level model comprising second level causal relationships and second level causal weights between the component fault codes and the failure modes; combine the first level model and the second level model to generate a graphical model; and determine, using the graphical model, one or more causal probabilities.