P24A2: Incomplete DPF regeneration is judged by soot remaining afterward

P24A2 identifies incomplete diesel particulate-filter regeneration. In Ford’s summary, the result is based on estimated soot remaining at the end of the regeneration event. It is not defined simply by whether the driver noticed heat or whether a regeneration request was issued.

Completion needs valid soot information

The monitor runs during each DPF regeneration cycle, with a maximum listed duration of forty minutes. Supporting exhaust-temperature, differential-pressure, and injection information must be satisfactory.

Ford also constrains the freshness of the closed-loop soot update: the listed time since the last update is limited at both the beginning and end of the event, with the end requirement much shorter. That makes an up-to-date soot estimate part of the evidence, rather than treating an old stored load value as interchangeable with a final assessment.

A finished event can still leave too much soot

The failure criterion is estimated soot above a threshold after regeneration. The summary does not publish that final soot threshold here, so a universal grams value should not be invented. Nor should every interrupted or unqualified event be assumed to meet this exact definition.

Useful verification preserves the event state, valid supporting sensors, and final soot-estimate timing. The source does not authorize repeated forced regeneration or identify the filter as the sole cause. It explains an unsuccessful end result that requires the correct vehicle diagnostic procedure before further regeneration or parts replacement is considered.

Source and applicability

This explanation follows Ford’s 2023–2024 diesel OBD summary. Match the vehicle’s engine and calibration before applying these monitor values; a generic code alone does not establish fitment. Ford PDF, page 52.