Powertrain, generic (extended)

P2572 Direct Ozone Reduction Catalyst Deterioration Sensor Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2572 points to a general fault in the circuit of a sensor meant to judge how much ozone-converting activity is left on a direct ozone reduction (DOR) catalyst, such as a coated radiator. CARB demands a real deterioration check only when the DOR credit is above 5 mg/mi NMOG on LEV III/IV vehicles (or half the NMOG standard on older ones); at or below that, the system merely has to notice a total loss of ozone reduction. BASF rates its PremAir NXT coating at a 5 mg/mi credit, which helps explain why no maker publicly documents P2572 or a dedicated deterioration sensor. Low, high and erratic signals have their own codes (P2574-P2576), the plausibility check is P2573. Driving is not affected.

Likely causes

Damaged wiring or connector at the DOR sensor
Failed deterioration sensor
Replacement radiator without the sensor fitted

Symptoms

  • Check engine light on
  • No effect on engine power or cooling

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€40–900
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

dor deterioration sensorsensor wiring

Related codes

P2573P2574P2575P2576P2577

References: law.cornell.edu, basf.com.