An expert diagnostic service system using a distributed architecture for generating expert diagnostic suggestions based on input received from a plurality of diagnostic systems. The expert service system collects data related to effective diagnostic results, such as effective fixes, corresponding to various symptoms/faults from a plurality of diagnostic systems via a data transmission network, and accumulates the number of each effective fix corresponding to each of the various symptoms. The expert service system then assigns at least one effective fix to one of the various symptoms based on a result of the accumulating step, such as the rank of the accumulated number of each fix. The expert service system uses the assigned fix corresponding to a symptom as expert suggestions.