Direct Ozone Reduction Catalyst Temperature Sensor Circuit Intermittent/Erratic
What it means
P2571 means the temperature sensor for the direct-ozone-reduction catalyst — a radiator-mounted catalyst used on some low-emission vehicles — is sending an intermittent or erratic signal. The ECM uses this reading to monitor the catalyst's operation for emissions purposes. Because the fault is intermittent, it most often traces to a loose or chafed connector rather than a failed sensor, and it does not affect how the engine drives.
Can I keep driving? Safe to drive; this is an emissions-monitoring sensor and does not affect how the engine runs.
Real-world scan data
Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.
Common symptoms
What you'll notice
- Check-engine light on
- Usually no noticeable driving symptom
- May fail an emissions-readiness or smog check
Common causes
Most likely first
- Loose or chafed sensor wiring or connector (common with intermittent faults)Likely
- Failing temperature sensorCommon
- Corroded connector contactsCommon
- Harness damage near the sensorLess often
How to diagnose & fix
Work through it in order
- Wiggle-test the wiring while watching the sensor's live data for dropouts.
- Inspect the sensor connector and harness for chafing or corrosion.
- Measure the sensor resistance against specification.
- Repair or clean the connector.
- Replace the sensor if the signal keeps cutting out.
FAQ
Quick answers
Is it safe to drive with P2571?+
Can I just clear P2571?+
Related codes
Read & clear P2571 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.