Code result
P209A
Reductant Injection Air Pressure Sensor B Circuit
Moderate severity
What it means
A general electrical fault is reported on reductant injection air-pressure sensor B — the second air-assist pressure sensor on dual-bank or dual-injector DEF systems.
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
Sensor failed
highOne of the most commonly reported causes for this code — check this first.
Harness fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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