Powertrain
generic / SAE
P249D
Closed Loop Reductant Injection Control At Limit Flow Too Low
With reductant injection running closed-loop the controller drives the dosing valve to maximum opening but cannot reach the required AdBlue flow.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 9D
Possible causes
- Reductant pump pressure low 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: 300–1500 €
- Estimated time: 1.5–5 h
- Component: reductant injector
- Component: reductant pump
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012