Powertrain
generic / SAE
P2C7A
SCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 2
The ECM detects that the conversion efficiency of the second SCR catalyst on bank 1 is below the calibrated threshold. NOx slip past catalyst 2 is too high.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / numberC / 7A
Possible causes
- Catalyst 2 aged or contaminated high
- Reductant dosing insufficient for cat 2 medium
Symptoms
- Check engine light on
- Failed emissions inspection
- Possibly slightly increased fuel consumption
- Sulfur (rotten egg) smell from exhaust under load
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 400–3000 €
- Estimated time: 2–10 h
- Component: scr catalyst b1 cat2
- Component: reductant dosing unit
- MIL / check engine light
- emissions-relevant
- drive cycle required
- limp mode possible
Sources
References
sae:J2012