5. The method of claim 4 , wherein outputting the categorized vehicle malfunction record to a user comprises outputting, if the categorized vehicle malfunction record comprises a low or medium probability, the one or more vehicle trouble records to a quality manager.
4. The method of claim 1 , comprising: receiving a vehicle malfunction record comprising one or more fleet vehicle system fault codes, one or more fleet vehicle component fault codes, and one or more fleet vehicle failure modes; categorizing the vehicle malfunction record based on the probability inferences, wherein determining, using the graphical model, one or more probability inferences comprises determining marginal probabilities based on the fleet vehicle system fault codes, the fleet vehicle component fault codes, and the fleet vehicle failure modes; and outputting the categorized vehicle malfunction record to a user.