OBD-II code · Powertrain (generic, extended)
P23B0 NOx Sensor Circuit Intermittent Bank 1 Sensor 3
Same as P23AC with intermittent or erratic signal. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Is it safe to drive with P23B0?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyIntermittent contact at connector
- Less likelyConnector with intermittent contact under vibration
- Less likelyHarness routed against vibrating component
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
Related codes
- P23ADNOx Sensor Circuit Range or Performance Bank 1 Sensor 3
- P23AENOx Sensor Circuit Low Bank 1 Sensor 3
- P23AFNOx Sensor Circuit High Bank 1 Sensor 3
- P23B1NOx Sensor Heater Control Circuit Open Bank 1 Sensor 3
- P23B2NOx Sensor Heater Control Circuit Low Bank 1 Sensor 3
- P23B3NOx Sensor Heater Control Circuit High Bank 1 Sensor 3
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.