OBD-II code · Powertrain (generic, extended)
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.
Is it safe to drive with P20E8?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyReductant pump weak or failed
- PossibleReductant filter clogged with crystals
- PossibleLeak in pressurised reductant line
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)
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–5 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Adblue Pump, Adblue Filter, Adblue Lines
Related codes
- P20E0Reductant Pressure Too Low
- P20E1Reductant Pressure Too Low
- P20E5Exhaust Gas Temperature Sensor 1/2 Correlation (Bank 2)
- P20E6Reductant Injection Air Pressure Too Low
- P20E7Reductant Injection Air Pressure Too High
- P20E9Reductant Pressure Too High
- P20EAReductant Pump Control Circuit Open
- P20EBReductant Reservoir Heater "A" Control Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.