Code result
P2BA6
NOx Exceedance - SCR NOx Catalyst Performance
High severity
What it means
NOx emissions are above the legal threshold and the ECU isolates the cause to the SCR NOx catalyst. Conversion efficiency is degraded — aged substrate, sulphur poisoning, or thermal damage.
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 substrate aged or contaminated
highOne of the most commonly reported causes for this code — check this first.
Thermal damage from prior over-temperature event
mediumA plausible cause — test and verify before replacing parts.
Related help
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