Code result
P20A5
Reductant Purge Control Valve A Stuck Closed
Moderate severity
What it means
Reductant purge control valve A is mechanically stuck closed — DEF lines cannot be vented at shutdown, increasing risk of freeze damage in winter.
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
Valve stuck closed mechanically
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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