Peugeot / Citroën – P20F6 00 Fault Code – DeNOx System Circuit: Leakage Detection
Fault code P20F6 00 indicates that the vehicle’s SCR (Selective Catalytic Reduction) system has detected a potential leak in the DeNOx fluid circuit. This is typically monitored by the system’s ability to pressurise and hold pressure within the AdBlue/DEF line. A leak or pressure loss will lead to failed emissions treatment, resulting in dashboard warnings and eventually a no-start condition if ignored.
This fault is commonly traced back to a faulty internal pump, leaking pressure lines, or a defect within the integrated pressure monitoring circuit inside the AdBlue tank module.
Which Peugeot and Citroën models are affected by P20F6 00?
This fault code is regularly encountered in the following BlueHDi models with SCR systems:
Diagnosis and solution – P20F6 00
Start by running a diagnostic scan to check the live data from the AdBlue pump and pressure sensor. During a leak test or priming cycle, observe whether the system can build and maintain pressure. If the system fails to hold pressure, the ECU will trigger fault code P20F6 00.
Inspect the following areas:
- Pressure lines and connectors for signs of leakage
- Electrical connectors for corrosion or loose pins
- The AdBlue tank itself for internal leakage or pump malfunction
If all external components appear in order, the root cause is likely a failure inside the AdBlue tank assembly, where the pressure circuit and pump are integrated.
Solution: Remanufacture at ACTRONICS
When facing persistent P20F6 00 faults and pressure-related issues, the most effective solution is to remanufacture the AdBlue tank module. ACTRONICS offers a high-quality remanufacturing service that addresses the known weak points in these systems.
During the process, all key components—including the internal pump, pressure sensor, and seals—are tested and replaced where needed. The result is a plug & play unit, remanufactured to OEM standards and returned with a 2-year warranty.
Choosing remanufacturing is not only more economical but also supports sustainability by reducing waste and unnecessary part replacement.