Code result
P20E6
Reductant Injection Air Pressure Too Low
Moderate severity
What it means
The DEF system air-assist pressure is below the required threshold — pump weak, line leak, or pressure-control valve stuck open.
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
Air pump weak
highOne of the most commonly reported causes for this code — check this first.
Leak in air line
mediumA plausible cause — test and verify before replacing parts.
Related help
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