Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. P2572 OBD-II Trouble Code: Direct Ozone Reduction Catalyst Deterioration Sensor Circuit 4

P2572 OBD-II Trouble Code: Direct Ozone Reduction Catalyst Deterioration Sensor Circuit 4

Check Engine Light

What the P2572 code means?

P2572 is an OBD-II generic code for the engine control module (ECM) detecting the ozone reduction catalyst has deteriorated or the sensor has failed. Some problems may be from a defective regeneration system on diesel engines.

What causes the P2572 code?

  • The ECM monitors the catalyst with sensors that measure the operation of the catalyst. When the catalyst sensor detects the catalyst, it will fall below specified limits for ozone reduction then it will turn on the Check Engine light and set the code P2572.

  • The catalyst is not operating correctly or the substrate inside it is contaminated or broken, allowing uncleaned exhaust to pass through it.

  • The catalyst sensor is not working to detect O2 levels and causing the failure.

What are the symptoms of the P2572 code?

  • The Check Engine light will be illuminated and the code is set in ECM memory as a fault. The light will stay on unless the problem goes away for at least 3 engine key cycles.

  • The vehicle may have reduced power due to the ECM failure strategy.

  • The vehicle may have rattling in the exhaust if the catalyst is broken apart.

  • The catalyst may glow red hot if the catalyst is plugged or partly melted.

How does a mechanic diagnose the P2572 code?

  • Scans for codes and documents the code in the ECM and looks at the freeze frame data for the problem before clearing the codes and retesting.

  • Runs the regeneration of the catalyst on diesel engines than have this option.

  • Checks all the O2 sensors for correct readings and notes any problems to be diagnosed.

  • Checks the exhaust for broken catalysts or O2 sensor wires burned.

  • Removes the catalyst sensor and looks for contaminations from a bad catalyst.

  • Checks the connector and wiring for corrosion causing an open or short in the sensor circuit.

Common mistakes when diagnosing the P2572 code

  • Clearing ECM memory codes before checking the freeze frame data for the main failure problem, so the failure may be duplicated and repaired

  • Failing to clear the ECM codes after the codes are fixed

  • Failing to run the regeneration for diesel engines before condemning the catalyst

How serious is the P2572 code?

Code P2572 is an indication that the ECM has got sensor signals that the catalyst is not cleaning the exhaust before it leaves the exhaust. This will fail an emission test.

What repairs can fix the P2572 code?

  • Run the regeneration to clean the catalyst in most newer diesel engines.
  • Repair the catalyst sensor connector pins for corrosion, melted or loose connections.
  • Replace the O2 sensor behind the catalyst.
  • Replace the catalyst and sensor.

Additional comments for consideration regarding the P2572 code

Code P2572 is for the catalyst sensor for some diesel engines and the code can be due to the regeneration of the exhaust and has not run or the system has problems that need fixing for it. The regeneration system cleans soot from the exhaust catalyst and allows it to work cleaning the exhaust of ozone pollutants again.

Need help with a P2572 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P0291OBD-II Trouble Code: Cylinder 11 Injector Circuit Low
P0291 code definition When your vehicle’s PCM registers the P0291 code, it means that a voltage reading came from the fuel injector circuit – for cylinder number 11’s fuel injector –...


Related questions

Q: Engine turns off when driving, cannot restart

Hello. It sounds like you have a voltage problem. It may be a bad connection at the battery or at one of the ground connections. Both will commonly occur. Any loss of voltage will cause some serious module communication issues....

Q: Q: Car stalling when stopped

The codes all reference engine misfires. Continued misfires can cause the catalyst to fail and block the exhaust. The past diagnosis you had that the coils could be bad was correct. The coils and plugs should be replaced first and...

Q: Looking for info about most common OBD2 Codes

There are two (at least) quite distinct issues in regard to your general request: The first is, once a check engine light illuminates, what are the most "frequent" codes that are stored and thence downloaded, that is what does THAT...