P202D: Reductant Leakage
Standardized SAE J2012 code · P20xx — Fuel & air metering and auxiliary emission controls
What does P202D mean?
A leak has been detected in the DEF (urea) supply system — usually by a pressure-decay test after pump shutdown, or by visible crystallisation around fittings.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Common causes
- High Cracked DEF line or fitting
- Medium Pump seal leaking
- Medium Injector mounting seal leaking
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P202D on the same make and model first.
P202D in the community
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