P207FReductant Quality Performance
The ECU has concluded that the AdBlue/DEF in the tank does not meet specification. Diagnosed by comparing expected NOx reduction against the dosed reductant volume — too much dosing for too little NOx drop indicates diluted or wrong fluid.
Can I keep driving? NO
STOP the vehicle in a safe place. Continuing to drive may cause serious engine damage or put your safety at risk.
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
- 1AdBlue diluted with water or wrong fluid filled NOx sensor drift gives false reductant-quality verdict
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Difficulty: medium. Estimated time: 0.5-3 hours. Estimated cost: €50-€
- 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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