P2573 — Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Range/Performance

P2573 — Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Range/Performance. A fault in the catalytic converter efficiency monitoring. The car is usually drivable while you plan the repair. Typical causes: oil or coolant entering the exhaust, engine misfires damaging the catalyst, exhaust leak ahead of the converter.

powertrain (engine/transmission)

Is it safe to drive?

Short-term driving is OK Usually safe to drive for a limited time: the car remains drivable, but emissions are elevated and fuel economy suffers. Do not postpone if you notice power loss, overheating of the exhaust, or a strong smell — a clogged converter can damage the engine.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm P2573 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the catalytic converter efficiency monitoring for damage, corrosion, chafing or poor contact.
Subsystem check Compare the direct ozone reduction catalyst deterioration sensor live reading against a known-good reference (specification or a correlated sensor) under the conditions from the freeze frame.
Subsystem check Compare upstream and downstream O2 sensor waveforms in live data — a healthy converter smooths the rear signal.
Subsystem check Check for exhaust leaks and rule out misfire codes before condemning the converter.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2573 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P2573 (parts and labor, USD, independent shop rates): Replace an oxygen sensor: $150–$450; Replace the catalytic converter: $800–$2,500; Repair an exhaust leak: $100–$350. Overall, fixing P2573 usually costs between $100 and $2,500. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

How do I diagnose P2573 myself?

Start with a scan: confirm P2573, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the direct ozone reduction catalyst deterioration sensor, and verify the suspect component against live data before buying parts.

What does OBD2 code P2573 mean?

Is it safe to drive with P2573?

Usually safe to drive for a limited time: the car remains drivable, but emissions are elevated and fuel economy suffers. Do not postpone if you notice power loss, overheating of the exhaust, or a strong smell — a clogged converter can damage the engine.

What are the symptoms of P2573?

Drivers most often notice: increased fuel consumption, rattling noise from under the car, sulfur or rotten-egg smell from the exhaust, slight loss of power at high rpm.

What is the most common cause of P2573?

The most common causes are: oil or coolant entering the exhaust, engine misfires damaging the catalyst, exhaust leak ahead of the converter.

What does P2573 mean?

Seeing P2573 on your scanner? The control unit has caught the catalytic converter efficiency monitoring operating outside its calibrated window. The formal description is “Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Range/Performance”, and the code is grouped under powertrain (engine/transmission) faults.

“Range/performance” means the signal from the direct ozone reduction catalyst deterioration sensor is electrically valid but does not match what the module expects for current operating conditions. The wiring is usually intact; the problem is a degraded component, a drifted sensor or a mechanical fault upstream.

This code does not appear from a single bad reading: the module must see the fault condition repeat under defined operating conditions before it turns on the warning light. The freeze frame captured with P2573 — engine load, rpm, temperature, speed — tells you exactly when the problem occurs, so reproduce those conditions when testing.

Common symptoms of P2573

increased fuel consumption
rattling noise from under the car
sulfur or rotten-egg smell from the exhaust
slight loss of power at high rpm
failed emissions test

What causes P2573?

mechanical fault that the sensor correctly reports
incorrect calibration after a module update or battery disconnect
degraded or drifting direct ozone reduction catalyst deterioration sensor
oil or coolant entering the exhaust
aged or contaminated catalytic converter
exhaust leak ahead of the converter
persistent rich or lean fuel mixture

How to diagnose P2573

Connect an OBD2 scanner, confirm P2573 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Visually inspect the wiring harness and connectors related to the catalytic converter efficiency monitoring for damage, corrosion, chafing or poor contact.
Compare the direct ozone reduction catalyst deterioration sensor live reading against a known-good reference (specification or a correlated sensor) under the conditions from the freeze frame.
Compare upstream and downstream O2 sensor waveforms in live data — a healthy converter smooths the rear signal.
Check for exhaust leaks and rule out misfire codes before condemning the converter.
Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2573 does not return.

How to fix P2573

Start with the cheapest and most common causes before replacing expensive parts:

Replace an oxygen sensor — $150–$450
Replace the catalytic converter — $800–$2,500
Repair an exhaust leak — $100–$350

How much does it cost to fix P2573?

Repair cost depends on which component actually failed. Typical scenarios for P2573 (parts and labor, USD, independent shop rates):

Replace an oxygen sensor: $150–$450
Replace the catalytic converter: $800–$2,500
Repair an exhaust leak: $100–$350

Overall, fixing P2573 usually costs between $100 and $2,500. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.