P2D1D
Reductant System Leak Detected – Small Leak
The SCR module detects a small leak in the reductant system based on pressure decay rate after dosing pause. Slow loss of DEF/AdBlue.
The SCR module detects a small leak in the reductant system based on pressure decay rate after dosing pause. Slow loss of DEF/AdBlue.
Common causes
- high
Fitting or connection loose
One of the most commonly reported causes for this code — check this first.
Typical part cost: $170-1650
- medium
Seal aged at injector or pump
A plausible cause — test and verify before replacing parts.
Typical part cost: $170-1650
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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 P2D1D mean?
P2D1D means "Reductant System Leak Detected – Small Leak". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2D1D?
fitting or connection loose; seal aged at injector or pump — 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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