Powertrain
generic / SAE
P229F
NOx Sensor Circuit Range/Performance Bank 1 Sensor 2
The downstream NOx sensor on bank 1 (after the SCR catalyst) returns implausible NOx readings during operation. Either the sensor is degraded or upstream chemistry is abnormal.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number2 / 9F
Possible causes
- NOx sensor aging high
- Low SCR efficiency medium
- Sensor element aged beyond calibration window 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: hard
- DIY: shop recommended
- Estimated cost: 400–1500 €
- Estimated time: 1–4 h
- Component: nox sensor
- Component: scr catalyst
- MIL / check engine light
- emissions-relevant
- drive cycle required
- limp mode possible
Sources
References
sae:J2012