With most vehicles the DPF warning light will illuminate to notify you that the unit is becoming blocked and requires regeneration. When conditions are met for regeneration, it will attempt to burn off the built up soot using either an active, or passive regeneration. If the regeneration is unable to occur or fails you may be treated to an additional warning light on your dash. This usually occurs when the DPF is blocked beyond the point at which a normal regeneration will clear it and indicates a garage visit is required.
