The P2216 code indicates that the engine control module has detected a voltage signal from the Bank 2 NOx (nitrogen oxide) sensor that is higher than the calibrated upper limit. This typically signifies an electrical open circuit or a short to voltage within the sensor or its wiring.
Internal failure of the sensor element or circuitry causing an out-of-range voltage signal.
Chafed, melted, or broken wires leading to the sensor, often caused by heat or mechanical wear.
Moisture or contaminants in the sensor plug causing high resistance or a poor electrical connection.
Air entering the exhaust stream upstream of the sensor, which can skew readings and trigger a circuit high code.
Internal fault in the engine control module's signal processing circuit.
In most cases, yes, as the sensor itself is the most frequent point of failure for this code.
The vehicle is usually drivable, but it will not pass emissions inspections and may lead to increased pollutant output.
No. While possible, PCM failure is extremely rare for NOx circuit codes; the sensor and wiring should be thoroughly exhausted as causes first.