Passive Regeneration: which statement is true?

• A. It requires operator interaction
• B. It cleans DPF under normal engine operation and does not require operator interactions
• C. It only occurs in parked mode
• D. It is initiated by the operator

Answer: (B)

Passive regeneration happens automatically as the engine operates, using the heat from normal exhaust flow to burn off soot in the diesel particulate filter. Because this cleaning occurs during regular driving and the engine management system handles it, no action from the driver is required. That makes it distinct from regen methods that need operator initiation or special conditions, such as parked-idle regeneration. The other statements imply driver involvement or parked-only operation, which doesn’t describe passive regeneration.