P2569: Direct Ozone Reduction Catalyst Temperature Sensor Circuit Low

P2569 means the radiator-mounted sensor of a DOR system (direct ozone reduction: a radiator coating that breaks down ozone in the incoming air) shows an electrical fault toward ground. According to VW's 2014 data books for the CC with 2.0 L TSI (CBFA, CCTA) and the Tiguan (CCTA), the sensor talks to the engine computer over a LIN line, and P2569 is set when that link fails because the line is grounded. The same books assign an open line or a short to battery voltage to P2570, while P2568 covers the identity and function check. Typical triggers are a chafed LIN wire touching the body or a corroded radiator connector. The car drives normally, but the stored code can fail an emissions inspection.

Medium severity. Can I keep driving?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.

Symptoms

Check engine light on
No change in driveability or engine temperature
Emissions inspection may be refused

Most likely causes

LIN wire to the radiator sensor chafed and shorted to ground
Water or salt corrosion in the radiator sensor connector
Internal short in the radiator sensor

What to check, in order

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

First resolve any misfire or fuel mixture codes
With the connector unplugged, check whether the signal wire is making contact with ground.
Look for exhaust leaks between the engine and the second sensor
Use live data to compare the signals from both oxygen sensors
Check for a blockage by measuring exhaust back pressure
Replace the catalytic converter only at the end of the diagnosis

Good to know

Repair difficulty: medium
It affects emissions.

What each character of P2569 means

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

Frequently asked questions

Can I keep driving with code P2569?

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 P2569?

The most common causes are: lIN wire to the radiator sensor chafed and shorted to ground; water or salt corrosion in the radiator sensor connector; internal short in the radiator sensor.

Related codes

Sources

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.