Code result
P20FA
Reductant Pump B Control Circuit/Open
Moderate severity
What it means
The control line driving DEF pump B is open. On large engines or dual-tank systems a second pump (B) supplements pump A; with B offline the system loses redundancy.
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
Pump motor winding open
highOne of the most commonly reported causes for this code — check this first.
Pin pushed back out of connector body
lowLess common, but worth ruling out after the more likely causes.
Cracked solder joint inside the module or sensor
lowLess common, but worth ruling out after the more likely causes.
Related help
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