Code result
P2D20
Reductant System Flow – Blocked
High severity
What it means
The SCR module detects fully blocked flow in the reductant system. No reductant reaches the injector despite commanded dosing.
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
Reductant injector clogged
highOne of the most commonly reported causes for this code — check this first.
Frozen reductant in cold weather
mediumA plausible cause — test and verify before replacing parts.
Related help
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