Code result
P20AB
Reductant Injection Air Pressure Control Valve Stuck Closed
High severity
What it means
Reductant air-pressure control valve mechanically stuck closed — air supply blocked, dosing fails.
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
Valve stuck closed
highOne of the most commonly reported causes for this code — check this first.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Component wear with age - mechanical play
lowLess common, but worth ruling out after the more likely causes.
Related help
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