Powertrain
generic / SAE
P249C
Excessive Time To Enter Closed Loop Reductant Injection Control
After cold start the AdBlue injection runs open-loop until SCR temperature is reached. The transition into closed-loop is taking longer than calibrated.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 9C
Possible causes
- SCR warm-up slow high
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: 200–1000 €
- Estimated time: 1–4 h
- Component: scr catalyst
- Component: reductant injection control
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012