Citroen AdBlue System Issues and Solutions

In Citroen models such as the C4, C5 Aircross, Berlingo, Grand C4 Picasso, and C3, the "Check AdBlue System" warning indicates a problem within your vehicle's emissions control system. What causes AdBlue failures? This warning usually results from low AdBlue fluid levels, issues within the SCR (Selective Catalytic Reduction) system, or sensor malfunctions. First, check the AdBlue level and top it up if necessary. If the issue persists, use a Citroen diagnostic tool to check for error codes and identify the root cause. Early resolution of these issues is crucial to maintaining your vehicle's performance.

AdBlue Warning Light On: What to Do?

If the AdBlue warning light is illuminated in your Citroen model, this indicates a problem with the AdBlue system. What should you do if your vehicle won’t start due to an AdBlue failure? First, check the AdBlue level and refill it if needed. If the light continues to stay on, there may be an issue with the quality of the AdBlue fluid. Old or low-quality AdBlue fluid can prevent the system from functioning efficiently. In such cases, you may need to drain the fluid and refill it with fresh AdBlue. What does AdBlue system failure mean? This indicates a fault in your vehicle’s SCR system that requires attention. Try resetting the system using a Citroen diagnostic tool. If the problem persists, professional service intervention may be necessary.

AdBlue Tank Full but Still Showing Warning: Causes and Solutions

If your AdBlue tank is full but the warning light remains on, this usually indicates another issue within the system. What causes AdBlue failures? Low-quality AdBlue fluid, crystallization of the fluid, or sensor malfunctions can trigger such warnings. Start by draining the old fluid and refilling the tank with fresh, high-quality AdBlue. If the warning continues, there might be an issue with the system’s sensors or injectors. In this case, use a Citroen diagnostic tool to identify the faults and perform the necessary repairs. How to fix AdBlue failure? Sensors or injectors may need to be replaced or repaired. Failing to address these issues can negatively impact your vehicle's emissions performance.

How to Reset the AdBlue System in Citroen Vehicles

Resetting the AdBlue system in Citroen vehicles may be necessary, especially if the AdBlue warning light remains on. How do you reset the AdBlue system? Citroen vehicles can reset the AdBlue system using Diagbox software. Diagbox is the official diagnostic and repair software for Citroen and Peugeot vehicles, allowing you to recalibrate the AdBlue system by connecting to the vehicle’s control unit.

Steps to Reset with Diagbox:

  • Install Diagbox Software: First, install the Diagbox software on your computer and ensure it is up-to-date. This software is the official diagnostic and repair tool for Citroen vehicles.
  • Connect the Vehicle: Connect your vehicle to the Diagbox system using an OBDII cable. This connection provides direct access to your vehicle’s electronic control unit.
  • Select the AdBlue System: Open the Diagbox software and select the AdBlue system from the menu. Here, you can view existing faults in the system and initiate the necessary reset procedures.
  • Initiate the Reset: Select the "AdBlue Reset" option and follow the on-screen instructions. This process will clear any existing errors and restore normal operation to the AdBlue system.
  • Conduct a Test Drive: After completing the procedure, take your vehicle for a test drive to ensure the AdBlue system is functioning correctly. If the warning light reappears, further mechanical inspection may be required.
This procedure can help resolve existing faults in the AdBlue system and reset it. However, if the problem persists, professional service support may be required.
DPF Failures: Causes and Solutions

In Citroen models, the DPF (Diesel Particulate Filter) system captures harmful particles from diesel engines to reduce emissions. However, over time, this filter can become clogged, leading to DPF failures. Why do DPF failures occur? The most common causes of DPF clogging include frequent short trips, using low-quality fuel, and lack of regular maintenance. Short trips prevent the DPF from regenerating (self-cleaning), leading to particle accumulation in the filter.

How to solve DPF failure? First, try initiating the DPF regeneration process by driving the vehicle at high speed for an extended period. This process helps burn off accumulated particles and clean the DPF. If this method doesn’t work, professional cleaning or replacement of the DPF may be necessary. Citroen diagnostic tools can also be used to clear error codes and manually start regeneration. If the DPF is completely blocked and cannot be cleaned, replacing the filter may be the best solution.

EGR Failures: Causes and Solutions

In Citroen models, the EGR (Exhaust Gas Recirculation) valve helps reduce emissions by redirecting some exhaust gases back into the combustion chamber. However, over time, the EGR valve can become clogged with carbon deposits, leading to failures. Why do EGR failures occur? Low-quality fuel, frequent short trips, and lack of maintenance can cause the valve to become clogged with carbon, preventing it from functioning correctly.

How to solve EGR failure? The first step may involve cleaning the EGR valve. A carbon cleaning process can remove deposits in the EGR valve, allowing it to function properly again. If the valve is severely clogged or damaged, it may need to be replaced. Citroen diagnostic tools should be used to check for error codes and assess the EGR valve's condition. Proper EGR system function is critical for controlling your vehicle's emissions, so it is important to address failures quickly.

Citroen AdBlue, DPF, and EGR Error Codes

In Citroen vehicles, the following are common error codes related to the AdBlue, DPF (Diesel Particulate Filter), and EGR (Exhaust Gas Recirculation) systems that you may encounter with a diagnostic tool:

AdBlue Error Codes:

  • P20E8: AdBlue pressure too low
  • P20F6: AdBlue level sensor fault
  • P2033: AdBlue heater malfunction
  • P2047: AdBlue injector circuit fault
  • P207F: SCR system efficiency low
  • P2200: NOx sensor circuit fault (pre-sensor)
  • P2202: NOx sensor circuit low (pre-sensor)

DPF Error Codes:

  • P2002: DPF efficiency low (particulate filter clogged)
  • P242F: DPF overloaded
  • P2453: DPF pressure sensor fault
  • P2458: DPF regeneration duration too long
  • P2463: DPF excessive particulate accumulation

EGR Error Codes:

  • P0400: EGR flow malfunction
  • P0401: EGR flow insufficient
  • P0402: EGR flow excessive
  • P0403: EGR valve circuit fault
  • P0404: EGR valve malfunction
  • P0405: EGR sensor circuit low
  • P0406: EGR sensor circuit high

These error codes indicate a problem within the vehicle's emissions control systems and can typically be detected using diagnostic tools. Each code points to a specific component or system issue, helping vehicle owners or technicians identify the root cause of the problem.

Proper diagnosis and timely repairs are essential to maintaining the vehicle's emissions performance and overall operational efficiency.