P2BA6
NOx Exceedance - SCR NOx Catalyst Performance
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.
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.
Common causes
- high
SCR catalyst substrate aged or contaminated
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-2200
- medium
Thermal damage from prior over-temperature event
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-2200
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P2BA6 mean?
P2BA6 means "NOx Exceedance - SCR NOx Catalyst Performance". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2BA6?
scr catalyst substrate aged or contaminated; thermal damage from prior over-temperature event — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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