What does code P23B1 mean?

Q: What does code P23B1 mean?

NOx Sensor Heater Control Circuit Open Bank 1 Sensor 3. P23B1 indicates that the powertrain control module (PCM) has detected an open circuit in the heater element of the nitrogen oxide (NOx) sensor located after the selective catalytic reduction (SCR) system on bank 1, sensor 3. The PCM monitors the heater circuit for expected current flow when commanded on, and an open circuit means no current is reaching the heater, preventing the sensor from reaching operating temperature.

DTC codes / P23xx · Ignition system and misfire / P23B1

P23B1NOx Sensor Heater Control Circuit Open Bank 1 Sensor 3

P23B1 indicates that the powertrain control module (PCM) has detected an open circuit in the heater element of the nitrogen oxide (NOx) sensor located after the selective catalytic reduction (SCR) system on bank 1, sensor 3. The PCM monitors the heater circuit for expected current flow when commanded on, and an open circuit means no current is reaching the heater, preventing the sensor from reaching operating temperature.

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.