OBD-II code · Powertrain (generic, extended)
P23BE NOx Sensor Performance Signal Biased or Stuck Low Bank 1 Sensor 3
Same as P23BD with the sensor stuck low.
Is it safe to drive with P23BE?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySensor element biased low
- Less likelySensor element aged beyond calibration window
- Less likelySensor element contaminated by oil, soot or coolant
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–2 h
- Emissions test
- Likely to fail
- Parts involved
- Nox Sensor B1s3
Related codes
- P23BBNOx Sensor Heater Resistance Bank 1 Sensor 3
- P23BCNOx Sensor Calibration Memory Bank 1 Sensor 3
- P23BDNOx Sensor Performance Signal Biased or Stuck High Bank 1 Sensor 3
- P23BFNOx Sensor Performance Slow Response Low to High Bank 1 Sensor 3
- P23C0NOx Sensor Performance Slow Response High to Low Bank 1 Sensor 3
- P23C1NOx Sensor Sensing Element Bank 1 Sensor 3
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.