Code result
P20E1
Reductant Pressure Too Low
High severity
What it means
The reductant (AdBlue/DEF) line pressure stays below the demanded value during dosing. The dosing system needs a stable supply pressure to inject metered amounts; without it the system cannot meet NOx targets.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Reductant pump worn or weak
highOne of the most commonly reported causes for this code — check this first.
Leak in pressure line
mediumA plausible cause — test and verify before replacing parts.
Inline filter clogged
mediumA plausible cause — test and verify before replacing parts.
Related help
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