P2567: Direct Ozone Reduction Catalyst Temperature Sensor Circuit
What to do
The car will drive exactly as normal and there is nothing here to feel. This equipment does not affect the engine at all — it is a catalytic coating on the radiator that converts ozone in the air passing through it into ordinary oxygen, and the sensor simply reports whether that coating is in its working temperature range.
The reason to fix it is that the emissions monitor cannot complete without it, so the vehicle may fail or be unable to take an emissions test even though it is running perfectly. Usually the fault is the connector or the wiring rather than the sensor.
One thing worth knowing if the radiator ever needs replacing: on a vehicle with this system the radiator carries the catalyst. A cheaper uncoated radiator will fit and cool perfectly well while quietly removing the equipment, so it is worth confirming the correct part is being used rather than one that merely fits.
What this code means
A fault in the circuit of the temperature sensor monitoring the direct ozone reduction catalyst.
This is one of the few devices on a vehicle that cleans air the vehicle did not dirty, and almost nobody knows their car has one.
Ground-level ozone is a pollutant in its own right — the main constituent of summer smog — and it exists in the air whether or not any particular car contributed to it. A direct ozone reduction catalyst is a catalytic coating applied to the radiator, and sometimes to the air conditioning condenser or charge air cooler alongside it. Air is drawn through those surfaces continuously while the car is driven, and ozone in it is converted to ordinary oxygen on contact. The air leaving the front of the car has less ozone in it than the air entering. In the certification schemes that led to these systems, that conversion counts toward the vehicle's emissions position, which is why the equipment exists at all.
The temperature sensor is there because the conversion only works within a temperature band. Too cold and the reaction is slow; too hot and the coating is not doing useful work either. The module needs to know whether the catalyst is in its window before it can credit the conversion or run the monitor that checks the system, so without a working sensor it cannot make that claim.
Nothing about the engine changes and the driver will notice nothing. What is at stake is an emissions monitor that cannot complete, which matters in a jurisdiction where that is tested.
One practical consequence deserves flagging, because it is a repair that silently removes an emissions device. The catalyst is a coating on the radiator, not a separate part in the exhaust. Fit an ordinary uncoated radiator — which will fit perfectly, cool perfectly and cost less — and the ozone reduction function is gone, with no obvious sign that anything was lost. On a vehicle equipped with this system the radiator is not an interchangeable part, whatever a catalogue lookup says.
Likely causes
Start here
- Corroded or loose connector · easy
- Damaged wiring harness · moderate
- Faulty ozone reduction catalyst temperature sensor · moderate
Less common
- Wiring shorted to ground · moderate
- Failed sensor reference voltage supply · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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