ENGINE COMPONENT AND LOCATION 119 Operational Mode Normal Mode The exhaust aftertreatment system (EATS) usually operates in one of five modes. Heat Mode Passive Regeneration Mode Active Regeneration Mode Service Mode In the Normal Mode, the engine is controlled by its regular calibration. However, the filters can be self-cleaning through passive regeneration. Heat Mode indicates that active regeneration is in process. In Passive Regeneration Mode, the engine creates sufficient exhaust temperature to convert the gases and regenerate (clean) the filters. In Active Regeneration Mode, exhaust temperature is artificially raised for short periods of time to convert the gases and clean the filters.
The applicable controller reacts to data from back pressure sensors to start and stop the active regeneration process. A system in Service Mode is being inspected for accumulation of soot and ash in the filters to determine whether they should be manually regenerated or removed for external regeneration.