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On-Board Diagnostic Tests

A diagnostic test is a series of steps which has a beginning and an end. The result of which is a pass or fail reported to the Diagnostic Executive. When a diagnostic test reports a pass result, the Diagnostic Executive records the following data:
^ The diagnostic test has completed since the last ignition cycle
^ The diagnostic test has passed during the current ignition cycle
^ The fault identified by the diagnostic test is not currently active

When a diagnostic test reports a fail result, the Diagnostic Executive records the following data:
^ The diagnostic test has completed since the last ignition
^ The fault identified by the diagnostic test is currently active
^ The fault has been active during this ignition cycle
^ The operating conditions at the time of the failure