Powertrain, generic (extended)

P2573 Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2573 means the deterioration sensor watching a DOR (direct ozone reduction) catalyst delivers a signal that is electrically within limits but does not fit the expected behaviour, for example a value that never changes with conditions or contradicts other inputs. Such a sensor would estimate how much of the catalytic coating on the radiator still destroys ozone, which CARB requires on vehicles claiming a large DOR credit. No manufacturer publishes P2573 or its test criteria, so the exact check is unknown; on comparable VW systems the analogous plausibility code P2568 fires on a failed identity or function check of the radiator sensor. P2572 is the generic circuit fault, P2574/P2575 the low and high signals. Driveability is unchanged; the MIL may come on.

Likely causes

Deterioration sensor drifting or stuck at one value
Non-original radiator with a sensor that does not match
Radiator face heavily fouled, skewing the sensor reading

Symptoms

  • Check engine light after several drive cycles
  • No change in how the car drives

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–900
Time0.5–3 h

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

Parts involved

dor deterioration sensor

Related codes

P2572P2574P2575P2576P2568

References: law.cornell.edu, static.nhtsa.gov.