Code result
P20F2
SCR NOx Catalyst Efficiency Below Threshold
High severity
What it means
SCR NOx Catalyst Efficiency Below Threshold (Bank 2): the control module has detected this fault condition.
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
SCR catalyst thermally aged
highOne of the most commonly reported causes for this code — check this first.
Catalyst poisoning from sulphur or oil ash
mediumA plausible cause — test and verify before replacing parts.
Related help
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