P23C1NOx Sensor Sensing Element Bank 1 Sensor 3
The downstream NOx sensor on bank 1 reports that its internal ZrO2 sensing element is no longer producing valid pumping currents - the element has lost its electrochemical response, typically because the active ceramic layer has been poisoned, cracked, or burnt out.
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
- 1Sensor element poisoned by silicone or sulphur
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Difficulty: medium. Estimated time: 1-1.8 hours. Estimated cost: €400-€
- 2Professional repair recommended
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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