Powertrain
generic / SAE
P2C79
NOx Adsorber - Sulfur Limit Exceeded
The ECM detects that the cumulative sulfur load on the NOx adsorber catalyst exceeds the calibrated threshold. Desulfation regeneration is required to restore catalyst function.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / numberC / 79
Possible causes
- Operation with high-sulfur fuel high
- Desulfation regen strategy disabled or failed medium
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: 200–2000 €
- Estimated time: 1–6 h
- Component: nox adsorber catalyst
- MIL / check engine light
- emissions-relevant
- drive cycle required
- limp mode possible
Sources
References
sae:J2012