Faulty NOx sensor on bank 2 sensor 1; Damaged or corroded wiring or connector at the sensor; Blown fuse or poor ground connection for the sensor circuit; Exhaust leak before the sensor allowing outside air to affect readings; Contaminated sensor element from oil or coolant entering the exhaust; Engine computer (PCM) software issue or internal fault

DTC codes / P22xx · Fuel and air metering (injector circuits) / P2215

P2215NOx Sensor Circuit Low Input (Bank 2 Sensor 1)

Q: What does code P2215 mean?

NOx Sensor Circuit Low Input (Bank 2 Sensor 1). P2215 means the engine computer has detected an abnormally low voltage signal from the upstream nitrogen oxide (NOx) sensor on bank 2, which is the side of the engine that does not contain cylinder number one. The sensor is responsible for reporting the concentration of nitrogen oxides in the exhaust so the computer can fine-tune the air-fuel mixture and reduce emissions.

P2215 means the engine computer has detected an abnormally low voltage signal from the upstream nitrogen oxide (NOx) sensor on bank 2, which is the side of the engine that does not contain cylinder number one. The sensor is responsible for reporting the concentration of nitrogen oxides in the exhaust so the computer can fine-tune the air-fuel mixture and reduce emissions.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Illuminated check engine light, often with no other noticeable symptoms
Reduced engine performance or a sudden drop in fuel economy
Rough idle or hesitation during acceleration
Increased nitrogen oxide emissions, which may cause a failed emissions test
In some vehicles, the engine may enter limp mode or limit power

Common causes, most likely first

Faulty NOx sensor on bank 2 sensor 1
Damaged or corroded wiring or connector at the sensor
Blown fuse or poor ground connection for the sensor circuit
Exhaust leak before the sensor allowing outside air to affect readings
Contaminated sensor element from oil or coolant entering the exhaust
Engine computer (PCM) software issue or internal fault

How to diagnose and fix it

Use an OBD-II scanner to confirm P2215 and check for any related codes
Visually inspect the NOx sensor, its wiring, and connector for damage or corrosion
Check the sensor circuit fuse and ground connections with a multimeter
Perform a voltage drop test on the sensor signal wire to rule out high resistance
Inspect for exhaust leaks upstream of the sensor and repair as needed
Replace the NOx sensor if testing confirms it is faulty
Clear the code and perform a road test to verify the repair

What a low NOx signal really means

A low voltage signal from the NOx sensor often indicates a wiring problem rather than a failed sensor, so always check the connector and harness before replacing parts.
Exhaust leaks before the sensor can dilute the exhaust sample with outside air, causing the sensor to report a false low reading and set this code.
Some vehicles require a software update to the engine computer to correct overly sensitive NOx sensor monitoring logic that triggers P2215 erroneously.
The NOx sensor on bank 2 sensor 1 is located on the exhaust system of the bank that does not contain cylinder number one, which is often harder to access and more prone to damage from road debris.

Can I keep driving with P2215?

You can usually continue driving with P2215, but avoid heavy acceleration and long trips until the fault is repaired, as prolonged driving may increase emissions and lead to further damage to the emissions system.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.