A systematic method can extrapolate tacit knowledge (hidden or subjective knowledge) so that it can become objective and discernable. This process focused on discovering causes of failures by extricating data from medical equipment service software cases closed by telephone by field service personnel. Their responses to observed failures were compared to troubleshooting guides in use by telephone support personnel to find new processes that would increase effectiveness of telephone support staff. We asked “What are indicators of device failure reported in technical support calls?” and then “What factors contribute to user reported device failures identified by callers to technical support?” A series of interviews with veteran personnel were used to validate responses from the “phone closed” cases along with ideas pulled from a review of documentation. Analysis of one hundred seventy three cases yielded over five hundred recommendations to make the telephone support personnel’s responses more accurate, consistent and reliable.