Powertrain
generic / SAE
P2D20
Reductant System Flow – Blocked
The SCR module detects fully blocked flow in the reductant system. No reductant reaches the injector despite commanded dosing.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / numberD / 20
Possible causes
- Reductant injector clogged high
- Frozen reductant in cold weather 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: medium
- DIY: shop recommended
- Estimated cost: 150–1500 €
- Estimated time: 1–6 h
- Component: reductant lines
- Component: reductant injector
- Component: reductant pump
- Component: scr module
- MIL / check engine light
- emissions-relevant
- drive cycle required
- limp mode possible
Sources
References
sae:J2012