Code result
P201A
Reductant Injection Valve Circuit Range/Performance
High severity
What it means
Reductant Injection Valve Circuit Range/Performance (Bank 2 Unit 1): the signal is implausible or outside the valid range. This valve doses reductant (DEF/AdBlue) into the exhaust for SCR NOx reduction.
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
DEF crystallisation clogs the dosing nozzle
highOne of the most commonly reported causes for this code — check this first.
DEF supply pressure below target
mediumA plausible cause — test and verify before replacing parts.
Valve coil ageing — slow response
mediumA plausible cause — test and verify before replacing parts.
Related help
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