Code result
P20E9
Reductant Pressure Too High
Moderate severity
What it means
Manufacturer-specific variant of the reductant over-pressure condition. The pressure exceeds the upper threshold during a defined operating window; on some platforms used in addition to P20E2 to flag a different test path.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Return line blocked or frozen
highOne of the most commonly reported causes for this code — check this first.
Pressure sensor reads high
mediumA plausible cause — test and verify before replacing parts.
Related help
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