Powertrain
generic / SAE
P20E8
Reductant Pressure Too Low
Pressure in the AdBlue/DEF supply line is below the target. Usually a failing reductant pump, a clogged filter, frozen lines, or a leak in the pressurised circuit.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / E8
Possible causes
- Reductant pump weak or failed high
- Reductant filter clogged with crystals medium
- Leak in pressurised reductant line 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: 200–1800 €
- Estimated time: 1–5 h
- Component: adblue pump
- Component: adblue filter
- Component: adblue lines
- MIL / check engine light
- emissions-relevant
- drive cycle required
- limp mode possible
Sources
References
sae:J2012