Powertrain
generic / SAE
P23C0
NOx Sensor Performance Slow Response High to Low Bank 1 Sensor 3
The NOx sensor on bank 1 sensor 3 takes longer than the diagnostic threshold to follow rising NOx levels - aged element.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number3 / C0
Possible causes
- Sensor element aged high
- Sensor element contaminated by oil, soot or coolant low
- 5V/reference voltage unstable under load low
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)
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 400–850 €
- Estimated time: 1–2 h
- Component: nox sensor b1s3
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012