1. A method to diagnose failures for a plurality of given machines, each machine having a corresponding plurality given hardware components, comprising: collecting a statistical reliability data for a plurality of the given machines and for a plurality of the given hardware components corresponding to each machine; constructing a case base database for each machine, having a plurality of case based database records, each of said records including a failed machine identifier field, a failed component identifier field, a failure description text field, and a solution record field; receiving an equipment problem description from a user, said description including a problem machine identifier and a problem description text; generating a statistical reliability based conditional statistical probability, for each of a plurality of the hardware components corresponding to the machine identified by said problem machine identifier, of said component having a failed state given that said machine has a failed state, based on said collected statistical reliability data; generating a case-based probability, for each of a plurality of the hardware components corresponding to the machine identified by said problem machine identifier, of said component having a failed state given that said machine has a failed state, based on comparing the problem description text received from the user to the failure description text field of a plurality of the case base database records; identifying a most probable failed hardware component from among the hardware components corresponding to the machine identified by said problem machine identifier, said identifying based on a combination of the generated statistical reliability based conditional probability of said identified component having a failed state given that said machine has a failed state, and said generated case-based probability of said component having a failed state.