Code result
P209E
Reductant Injection Air Pressure Sensor A/B Correlation
Moderate severity
What it means
The two reductant injection air-pressure sensors A and B disagree by more than the allowed tolerance — one is reading off, or there is a real pressure imbalance between the two air-assist branches.
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
One sensor drifts relative to the other
highOne of the most commonly reported causes for this code — check this first.
Real imbalance between air branches
mediumA plausible cause — test and verify before replacing parts.
Related help
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