Fault code P20EE refers to a problem in the exhaust system, specifically SCR NOx Catalyst Efficiency Below Threshold, which means the NOx catalyst is not working efficiently enough. This fault is common in diesel vehicles with AdBlue technology.
When P20EE is detected, it means the system is unable to convert enough nitrogen oxides, also known as NOx. This can lead to increased emissions and loss of power. The cause is usually contamination of the catalyst, faulty NOx sensors or problems with AdBlue injection.
In P20EE Volkswagen or P20EE VW models, including the P20EE VW Transporter, the fault is often caused by poor AdBlue atomisation or a defective NOx sensor before or after the catalyst. Regular use of high-quality AdBlue and timely maintenance can help prevent this.
The same fault code is also found in other brands, such as DTC P20EE Peugeot. In those cases, it is usually caused by an ageing SCR catalyst or a fault in the dosing unit.
In all cases, it is important to read the fault codes, check the AdBlue system and, if necessary, replace the NOx sensor or catalyst to prevent further damage.
