1. A method to analyze errors in a system, the system having a plurality of resources with replaceable units, a display, a processor, and memory means for storing decision trees, data structures, threshold alarm tasks, failing resource manager tasks and error analysis tasks, the resources including a diagnostics card having a processor and memory means for storing resource analysis tasks, and communication resources, the method comprising the steps of: (a) testing said resources intermittently by said error analysis tasks invoking a card analysis task on said diagnostics card to test for an error in said communication resources in said system; (b) detecting an error and invoking an appropriate error analysis task to process said error; (c) processing said error by said appropriate error analysis task to isolate said error to a replaceable unit by automatically traversing said decision trees; (d) writing data to record said error in said data structures in said memory means of said system; (e) invoking said failing resource manager tasks to retest said replaceable unit; (f) invoking said threshold alarm tasks to determine an effect of removal of said replaceable unit on said system; (g) indicating to said failing resource manager tasks if said replaceable unit can be removed; (h) removing said replaceable unit from service if said retest detects said error and said threshold alarms tasks indication is favorable; (i) retesting said replaceable unit to detect a return to normal operation; (j) returning said replaceable unit to service if normal operation is determined; and (k) displaying a message based on said error on said display of said system.