Code result
P2D1D
Reductant System Leak Detected – Small Leak
High severity
What it means
The SCR module detects a small leak in the reductant system based on pressure decay rate after dosing pause. Slow loss of DEF/AdBlue.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Fitting or connection loose
highOne of the most commonly reported causes for this code — check this first.
Seal aged at injector or pump
mediumA plausible cause — test and verify before replacing parts.
Related help
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