P056DReductant Control Module System Voltage
The reductant (AdBlue) control module reports its supply voltage outside the calibrated window. Reductant dosing is suspended until voltage returns to range, which can drive NOx emissions out of compliance.
Can I keep driving? With caution
You can drive to the shop, but do not postpone the repair. The problem may worsen and damage other components.
Sistema Afectado
Motor · Powertrain
La falla pertenece al grupo motopropulsor (motor y gestión electrónica).
Espacio para vendedores de repuestos
Aún no hay un anunciante en este espacio.
Symptoms You Will Notice
What you may observe when this code appears
- Check engine light or NOx warning on AdBlue/DEF level or quality warning Possible no-start countdown after ignore period Failed emissions inspection (NOx)
Possible Causes
The components or conditions that trigger this code
- 1Supply voltage low
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Difficulty: medium. Estimated time: 0.6-2 hours. Estimated cost: €120-€
- 2DIY possible
Note: This information is for general reference. For precise diagnostics and safety repairs, always consult a certified mechanic.
Estimated Cost
Approximate range in USD (varies by region and shop)
Varies by diagnosis
* Diagnosis only: $50–$150
Quick Info
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