P2C7A
SCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 2
The ECM detects that the conversion efficiency of the second SCR catalyst on bank 1 is below the calibrated threshold. NOx slip past catalyst 2 is too high.
The ECM detects that the conversion efficiency of the second SCR catalyst on bank 1 is below the calibrated threshold. NOx slip past catalyst 2 is too high.
Common causes
- high
Catalyst 2 aged or contaminated
One of the most commonly reported causes for this code — check this first.
Typical part cost: $440-3300
- medium
Reductant dosing insufficient for cat 2
A plausible cause — test and verify before replacing parts.
Typical part cost: $440-3300
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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 P2C7A mean?
P2C7A means "SCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 2". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2C7A?
catalyst 2 aged or contaminated; reductant dosing insufficient for cat 2 — 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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