P2572
Direct Ozone Reduction Catalyst Deterioration Sensor Circuit
General electrical fault on the DOR catalyst deterioration sensor circuit. This sensor estimates the remaining ozone-conversion capacity of the DOR coating — coating worn off the radiator surface, contaminated by salt or grime, or thermally aged. Without a valid signal the deterioration monitor is disabled.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Failed emissions inspection
- Possibly slightly increased fuel consumption
- Sulfur (rotten egg) smell from exhaust under load
Common causes
Ordered by how often each turns out to be the cause.
- Open or shorted wiringCommon
Parts involved
- Dor Deterioration Sensor
- Sensor Wiring
P2572 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.