A control system for a vehicle includes a first vehicle system including a plurality of components and a controller. The controller monitors diagnostic data for the plurality of components of the first vehicle system and outputs a two-state status indicator for each of the components of the first vehicle system. States of the two-state status indicator include a failing state and a not failing state. A control module is configured to receive the two-state status indicator and the diagnostic data from the first vehicle system and to convert the two-state status indicator into a three-state status indicator. The three-state status indicator includes a pass state, a fail state and an indeterminate state. The control module is further configured to alter an engine operating parameter based on the three-state status indicator.