What does code P23AF mean?

Q: What does code P23AF mean?

NOx Sensor Circuit High Bank 1 Sensor 3. P23AF indicates that the powertrain control module has detected an abnormally high voltage signal from the third nitrogen oxide (NOx) sensor located on bank 1 of the engine. The sensor circuit is reporting a voltage above the expected range, which the computer interprets as a fault in the sensor itself, its wiring, or the reference voltage supply.

DTC codes / P23xx · Ignition system and misfire / P23AF

P23AFNOx Sensor Circuit High Bank 1 Sensor 3

P23AF indicates that the powertrain control module has detected an abnormally high voltage signal from the third nitrogen oxide (NOx) sensor located on bank 1 of the engine. The sensor circuit is reporting a voltage above the expected range, which the computer interprets as a fault in the sensor itself, its wiring, or the reference voltage supply.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

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