P2571: Direct Ozone Reduction Catalyst Temp Sensor Circuit Intermittent/Erratic
The P2571 code indicates an intermittent or erratic signal from the Direct Ozone Reduction (DOR) catalyst temperature sensor circuit. This sensor monitors the temperature of the catalyst that reduces ozone in the exhaust system. An erratic signal can be caused by a faulty sensor, damaged wiring, poor electrical connections, or a malfunctioning engine control module (ECM). This issue may affect emissions and trigger the check engine light.
1. Most Common Causes
- Loose, corroded, or high-resistance electrical connections in the sensor circuit
- Damaged, chafed, or intermittently shorted wiring (to ground or voltage)
- Faulty or deteriorated direct ozone reduction catalyst (DORC) temperature sensor
- Bent, spread, or poorly mating terminals at the sensor connector
- Intermittent internal PCM failure (less common)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Possible failed emissions test
- Reduced fuel economy (in some cases)
- No noticeable drivability issues typically
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for other related codes.
Step 2: Visually inspect the DOR catalyst temperature sensor and its wiring for damage, corrosion, or loose connections.
Step 3: Test the sensor's resistance and voltage output using a multimeter and compare to manufacturer specifications.
Step 4: Check for intermittent issues by wiggling the wiring harness while monitoring the sensor signal with a scan tool.
Step 5: If sensor and wiring are okay, test the ECM for proper signal reception and consider reprogramming or replacement if necessary.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, it is generally safe to drive, but the check engine light will be on and the vehicle may fail an emissions test. It's best to diagnose and repair the issue promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and sensor replacement, but can be higher if wiring repairs or ECM replacement is needed.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.