P2572 — Direct Ozone Reduction Catalyst Deterioration Sensor Circuit #

Note: The code description may vary depending on the vehicle manufacturer.

• Direct Ozone Reduction Catalyst Deterioration Sensor Circuit (Generic/OEM)
• Ozone Reduction Catalyst Sensor Circuit Malfunction (Toyota/Lexus)
• Ozone Catalyst Sensor Circuit Fault (Honda/Acura)
• Ozone Converter Catalyst Efficiency Sensor Circuit (Mazda)

Summary of DTC P2572 #

P2572 is an OBD-II diagnostic trouble code (DTC) that signals an issue detected by the vehicle’s onboard computer (ECU) regarding the Direct Ozone Reduction Catalyst Deterioration Sensor Circuit. This sensor monitors the efficiency of the ozone reduction catalyst, a component designed to reduce ozone emissions in the exhaust system. When the sensor circuit malfunctions, the ECU cannot accurately determine the catalyst’s condition, which may impact emissions control. While not a common code, it is becoming more prevalent in modern vehicles equipped with advanced emission technologies. Understanding and addressing this fault promptly helps ensure both compliance with environmental standards and proper engine performance.

Common Symptoms for DTC P2572 #

The presence of code P2572 often results in subtle symptoms, as the ozone reduction catalyst is primarily related to emissions rather than core drivability. However, some drivers may notice the following:

• Illuminated Check Engine Light (MIL)
• Failed emissions test or inspection
• Possible reduction in fuel efficiency (rare)
• Stored pending codes related to emissions systems
• No noticeable change in engine performance in most cases

Probable Causes for Code P2572 (Most to Least Common) #

The root causes of P2572 are commonly found within the sensor circuit or exhaust components. The most frequent culprits include:

1. Faulty ozone reduction catalyst deterioration sensor
2. Damaged or corroded sensor wiring/connectors
3. Open or short circuit in the sensor circuit
4. Failed ozone reduction catalyst (rare)
5. ECU/PCM software issue or failure (least common)

Step-by-Step Diagnosis for P2572 #

Proper diagnosis of P2572 requires a methodical approach to avoid unnecessary parts replacement. Follow these steps:

• 1. Verify the code with a professional-grade OBD-II scan tool and check for related codes.
• 2. Visually inspect the ozone reduction catalyst sensor and all associated wiring/connectors for damage or corrosion.
• 3. Test sensor circuit continuity and resistance with a multimeter according to OEM specifications.
• 4. Check for proper voltage supply and ground at the sensor connector.
• 5. Use a scan tool to monitor live data from the sensor; compare with manufacturer reference values.
• 6. If all checks pass, consider software updates or rare ECU/PCM faults as the cause.

Possible Repairs for P2572 #

Once the cause is identified, targeted repairs will resolve P2572. Typical solutions include:

• Replacing the ozone reduction catalyst deterioration sensor if found faulty
• Repairing or replacing damaged wiring or connectors
• Correcting open or short circuits in the sensor circuit
• Replacing the ozone reduction catalyst itself (only if confirmed defective)
• Updating or reprogramming the ECU/PCM as per OEM bulletins

Is It Safe to Drive with Code P2572? #

In most cases, driving with code P2572 is safe for short periods, as it typically does not affect core engine performance or drivability. However, the vehicle will not pass an emissions inspection and may contribute to higher ozone emissions. Extended operation with this code active is not recommended, especially in areas with strict emissions laws or if other related DTCs are present.

Vehicles Most Commonly Affected by P2572 #

While P2572 can appear on any modern vehicle equipped with an ozone reduction catalyst, it is most frequently observed in:

• Toyota and Lexus hybrid and gasoline models (mid-2010s+)
• Honda and Acura vehicles with advanced emission controls
• Mazda Skyactiv models
• Some Ford and GM vehicles post-2015
• Late-model Subaru and Nissan vehicles (less frequent)

Common Mistakes & Best Practices for P2572 #

Misdiagnosis or overlooking simple faults can lead to unnecessary repairs. To avoid pitfalls:

• Do not replace the ozone reduction catalyst before confirming sensor and wiring integrity.
• Always check for technical service bulletins (TSBs) related to P2572 for your specific vehicle.
• Use OEM replacement sensors to ensure compatibility and durability.
• Be cautious with aftermarket scan tools; verify readings with professional equipment if possible.
• Clear codes only after repairs and confirm with a drive cycle that the fault does not return.

Express FAQ for DTC P2572 #

Q: Can a bad ozone reduction catalyst sensor cause engine damage?
A: No, but it can lead to increased emissions and failed inspections. Engine performance is rarely affected.

Q: Does disconnecting the battery clear P2572?
A: Temporarily, but the code will return if the underlying issue is not fixed. Proper diagnosis and repair are required for a permanent solution.