Code result
P204A
Reductant Pressure Sensor Circuit
Moderate severity
What it means
A general electrical fault is reported on the DEF system pressure sensor — used to verify pump priming, line pressure, and to detect leaks via pressure-decay tests.
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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