What does code P23B8 mean?

Q: What does code P23B8 mean?

NOx Sensor Heater Sense Circuit Low Bank 1 Sensor 3. P23B8 indicates the powertrain control module has detected an abnormally low voltage on the heater sense circuit for the third nitrogen oxide (NOx) sensor on bank 1. The sensor's internal heating element is not drawing the expected current, so the computer cannot confirm the heater is functioning and may not trust the sensor's emissions readings.

DTC codes / P23xx · Ignition system and misfire / P23B8

P23B8NOx Sensor Heater Sense Circuit Low Bank 1 Sensor 3

P23B8 indicates the powertrain control module has detected an abnormally low voltage on the heater sense circuit for the third nitrogen oxide (NOx) sensor on bank 1. The sensor's internal heating element is not drawing the expected current, so the computer cannot confirm the heater is functioning and may not trust the sensor's emissions readings.

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.