P2573
Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Range/Performance
The DOR deterioration sensor is electrically intact but its readings drift or do not match the model — for example a deterioration value that does not move with km/h driven, or moves implausibly fast.
- 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.
- Aged sensor with offset driftCommon
- Sensor element aged beyond calibration windowLess likely
- Sensor mounting loose - signal dampingLess likely
Parts involved
- Dor Deterioration Sensor
P2573 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.