P2D5A

Reductant Level Sensor A/B Correlation

Moderate severity

The signals of the reductant level sensors A and B do not correlate within the calibrated tolerance. One sensor drifts or installation offset between channels.

Common causes

One sensor characteristic drifted
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $90-390
Harness incorrectly swapped between channels
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $90-390
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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

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Frequently asked questions

What does P2D5A mean?

P2D5A means "Reductant Level Sensor A/B Correlation". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P2D5A?

one sensor characteristic drifted; harness incorrectly swapped between channels — 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?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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