P2572: Direct Ozone Reduction Catalyst Deterioration Sensor Circuit

What it means

The Direct Ozone Reduction Catalyst Deterioration Sensor Circuit code indicates a fault in that sensor circuit. The code does not by itself establish that the catalyst coating is worn or contaminated.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test

How it works

The DOR catalyst deterioration sensor circuit carries information the engine control module uses to assess the direct ozone reduction catalyst system. P2572 sets when the circuit has an electrical fault; the code alone does not prove the catalyst itself has deteriorated.

Common causes

Most likely first.

1. Open or shorted sensor-circuit wiring
2. Loose or corroded connector
3. Faulty direct ozone reduction catalyst deterioration sensor

Symptoms

• Check engine light

How to diagnose it

1. Check freeze-frame data and scan-tool data for the DOR deterioration sensor circuit, noting whether the reading is missing or implausible.
2. Locate the sensor using the vehicle information and inspect its connector and harness for loose pins, corrosion, opens, or shorts.
3. Check the circuit's power or reference, ground or return, and signal paths using the wiring diagram for that vehicle.
4. Test continuity and shorts to ground or power in the sensor wiring, comparing results with the manufacturer's specifications.
5. If the circuit wiring and connections pass, test the DOR deterioration sensor before suspecting the control module.

Common fixes

• Repair an open or shorted sensor-circuit wire.
• Clean, tighten, or replace a loose or corroded connector.
• Repair damaged harness insulation and restore proper routing.
• Replace the DOR deterioration sensor if it fails its specified test.

Can I keep driving?

A check-engine light is the stated symptom, and no limp mode is indicated, so driving is generally possible if the vehicle runs normally. The DOR catalyst monitor may be unavailable until the circuit fault is fixed.