P2570: Direct Ozone Reduction Catalyst Temperature Sensor Circuit High

P2570 is the high-side electrical fault of the sensor fitted to a DOR radiator, the ozone-converting coated radiator found on some low-emission petrol cars. VW's 2014 Tiguan book (2.0 L TSI, CCTA) logs it when LIN communication with the sensor breaks down because the line is interrupted or carries battery voltage; the 2014 CC book applies the same criterion to its CBFA and CCTA engines. A connector left unplugged after radiator work, a broken wire or a dead sensor are the usual reasons. VW Tech Tip 19-12-01 adds that a new radiator is delivered with this sensor loose, so it has to be glued on and connected. P2569 is the shorted-to-ground case. Cooling and driveability are unaffected; the MIL and inspection readiness are what matter.

Symptoms

• Check engine light, often right after radiator work
• Engine runs and cools normally

Most likely causes

• Sensor not connected or not fitted after radiator replacement
• Broken LIN wire or loose terminal
• Radiator sensor failed

What to check, in order

Start with the simplest. You can tick off each step.

1. First resolve any misfire or fuel mixture codes
2. Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
3. Look for exhaust leaks between the engine and the second sensor
4. Use live data to compare the signals from both oxygen sensors
5. Check for a blockage by measuring exhaust back pressure
6. Replace the catalytic converter only at the end of the diagnosis

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P2570 means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• 5: Speed and idle
• 70: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2570?

You can usually keep driving, unless you notice a loss of power, which may point to a blockage. The car may not pass an emissions inspection.

What causes code P2570?

The most common causes are: sensor not connected or not fitted after radiator replacement; broken LIN wire or loose terminal; radiator sensor failed.

Related codes

• P2567Direct Ozone Reduction Catalyst Temperature Sensor Circuit
• P2568Direct Ozone Reduction Catalyst Temperature Sensor Circuit Range/Performance
• P2569Direct Ozone Reduction Catalyst Temperature Sensor Circuit Low
• P2571Direct Ozone Reduction Catalyst Temperature Sensor Circuit Intermittent/Erratic

Sources

• static.nhtsa.gov: MC 10122272 9999
• static.nhtsa.gov: MC 10119356 9999
• static.nhtsa.gov: MC 10122979 9999

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.