OBD-II code · Powertrain (generic, extended)
P23AE NOx Sensor Circuit Low Bank 1 Sensor 3
Same as P23AC with the signal voltage below the plausible range. 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 P23AE?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySignal shorted to ground
- Less likelyConnector pins corroded - high contact resistance
- Less likelyHarness chafing through insulation
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
- P23ABNOx Sensor Processor Performance Bank 1 Sensor 3
- P23ACNOx Sensor Circuit Bank 1 Sensor 3
- P23ADNOx Sensor Circuit Range or Performance Bank 1 Sensor 3
- P23AFNOx Sensor Circuit High Bank 1 Sensor 3
- P23B0NOx Sensor Circuit Intermittent Bank 1 Sensor 3
- P23B1NOx Sensor Heater Control Circuit Open Bank 1 Sensor 3
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.