O2 Sensor Exhaust Sample Error Bank 2 Sensor 1
Diagnostic trouble code P2415 indicates that the powertrain control module (PCM) has detected an exhaust sample error from the upstream oxygen sensor on Bank 2. This means the sensor is not providing a plausible or expected reading during the exhaust sampling process, often due to an exhaust leak or sensor malfunction.
While not immediately dangerous, this code affects the engine's air/fuel mixture. Prolonged driving can lead to poor fuel economy, increased emissions, and potential damage to the catalytic converter.
Common symptoms
- Illuminated Check Engine Light
- Decreased fuel efficiency
- Rough idle or engine hesitation
- Noticeable exhaust smell
- Failed emissions test
Likely causes
- Exhaust leak near the Bank 2 Sensor 1 oxygen sensor
- Faulty Bank 2 Sensor 1 oxygen sensor
- Damaged or corroded wiring or connector for the oxygen sensor
- Vacuum leak affecting the engine's air/fuel ratio
- Faulty mass airflow (MAF) sensor or manifold absolute pressure (MAP) sensor
- Powertrain Control Module (PCM) failure (rare)
What to check before replacing parts
Visually inspect the exhaust system near Bank 2 Sensor 1 for leaks.
Look for: Look for soot marks, cracks, or listen for a ticking sound that indicates an exhaust leak before or near the sensor.
Inspect the wiring and connector for the Bank 2 Sensor 1 oxygen sensor.
Look for: Check for melted, chafed, or broken wires, and ensure the connector is secure and free of corrosion.
Monitor the Bank 2 Sensor 1 oxygen sensor data using a scan tool.
Look for: Observe the sensor's voltage output; it should rapidly fluctuate between 0.1V and 0.9V when the engine is at operating temperature. A sluggish or fixed reading indicates a faulty sensor.
Check for intake vacuum leaks.
Look for: Listen for hissing sounds or use a smoke machine to find unmetered air entering the intake manifold, which can skew O2 sensor readings.
Test the oxygen sensor heater circuit.
Look for: Use a multimeter to check for proper voltage and ground at the sensor heater circuit pins, and verify the sensor's internal heater resistance is within factory specifications.
This page explains the generic P2415 definition and is general reference information, not a diagnosis for your specific vehicle. Actual causes, severity, and repairs vary by make, model, engine, and mileage — always confirm with a scan tool and a qualified technician before replacing parts.
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