P2574
Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Low
Emissions monitoring
Generic OBD-II
Low
What it means
P2574 means the ECM detected low voltage (a short-to-ground or open) in the circuit for the direct-ozone-reduction catalyst deterioration sensor — an emissions monitor found on some vehicles that use an ozone-reducing radiator coating. It's a monitoring/wiring fault that doesn't affect how the engine runs, though it should be fixed for emissions readiness.
Low
Can I keep driving? Yes — this is an emissions-monitoring circuit fault and does not affect how the engine runs.
Common symptoms
What you'll notice
- Check-engine light on
- No noticeable change in how the vehicle drives
- An emissions readiness monitor may not complete
Common causes
Most likely first
- Short-to-ground or open in the deterioration sensor circuitLikely
- Corroded or loose connector at the sensorCommon
- Faulty direct-ozone-reduction catalyst deterioration sensorCommon
- Rarely, an ECM faultLess often
How to diagnose & fix
Work through it in order
- Scan for codes and record freeze-frame data.
- Inspect the sensor wiring and connector for a short-to-ground or open.
- Measure the sensor circuit voltage against specification.
- Repair the wiring or replace the sensor if faulty.
- Clear the code and re-test.
FAQ
Quick answers
Is it safe to drive with P2574?+
Yes. It's an emissions-monitoring fault that doesn't affect engine performance, though it should be fixed to pass an emissions test.
Can I just clear P2574?+
It will return until the low-circuit fault or sensor is repaired.
Related codes
Often seen with P2574
Read & clear P2574 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX