OBD-II code · Powertrain (generic, extended)

P23AD NOx Sensor Circuit Range or Performance Bank 1 Sensor 3

Same as P23AC with the signal in plausible range yet not matching the engine model.

Is it safe to drive with P23AD?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelySensor element drifted

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
1–1.8 h
Emissions test
Likely to fail
Parts involved
Nox Sensor B1s3

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.