P2D45
Reductant Temperature Too Low
The reductant temperature is below the calibrated minimum. DEF/AdBlue may not flow correctly through the dosing system - heater fault or extreme cold weather.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
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
Ordered by how often each turns out to be the cause.
- Reductant heater failedCommon
- Extreme ambient coldPossible
Parts involved
- Reductant Tank
- Reductant Heater
- Reductant Lines
P2D45 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.