AdBlue problem on Bucher Municipal Optifant sweeper
Introduction: Bucher Municipal Optifant sweepers, powered by the JCB 444 engine, are essential for urban cleaning. However, like any sophisticated piece of equipment, they can run into problems, particularly with the AdBlue system. When faults occur, they can seriously affect the machine's performance, from power reduction to downgrading. This article will guide you through the steps involved in diagnosing, reprogramming and resolving AdBlue problems on these sweepers, highlighting common faults and effective intervention methods.
Features of the Delphi DCM3.3 ECU and the Bosch DCU17CV51 DCU: 2019 Bucher Municipal Optifant sweepers use two main ECUs: the Delphi DCM3.3 for the engine and the Bosch DCU17CV51 for AdBlue system management. The Delphi DCM3.3 ECU is responsible for managing engine performance, fuel injection and emissions compliance. It uses sensors to monitor various engine functions and adjusts parameters in real time to optimize performance and efficiency. On the other hand, the Bosch DCU17CV51 specifically manages the AdBlue system, controlling the injection of the additive into the exhaust stream to reduce nitrogen oxide emissions. These ECUs work together to ensure optimum performance.
ECU and DCU reprogramming procedure :
Step 1: Connecting and reading data : The first step in reprogramming is to connect the specific diagnostic tools to the ECUs. For the Delphi DCM3.3 ECU, connection is via OBD (On-Board Diagnostics), a standardized port providing access to vehicle data. Once connected, the diagnostic tool reads any fault codes present, as well as engine mapping data. In the case of the Bosch DCU17CV51 DCU, reading is carried out using the bench method, by connecting directly to the ECU pins and supplying an external, stabilized power supply. This method provides direct and complete access to the ECU's flash memory, essential for precise reprogramming. The initial reading of data and fault codes identifies the exact problems affecting the AdBlue system, paving the way for the development of a new operating program.
Step 2: Developing the new program: Having identified the faults and extracted the necessary data, the next step is to develop a new program for the vehicle. This process involves analyzing engine mapping data and microcontroller memory to understand the necessary adjustments. Technicians use specialized software to modify the operating parameters of the engine and AdBlue system, aiming to correct identified faults and optimize performance. The new program is designed to improve emissions management, increase engine efficiency over the long term and thus put an end to all AdBlue problems on JCB engine sweepers.
Step 3: Flashing the ECU and DCU: Flashing, or reprogramming, is the step where the new program is written to the ECU's memory. For the Delphi DCM3.3 ECU, this is done via OBD. The diagnostic software loads the new program into the ECU's flash memory, replacing the old mapping. For the Bosch DCU17CV51, reprogramming is carried out using the bench method, with a direct connection to the ECU pins and a stabilized power supply. This method guarantees precise, uninterrupted writing. It is crucial to check that power supplies, ground, ADCs and voltage are correctly connected, to avoid damage to the ECUs. Once flashing is complete, the systems are restarted to check that the new program is working correctly and that all fault codes have been resolved.
Once this has been checked, we move on to a visual inspection of the dashboard to ensure that there are no warning lights or error messages. Finally, carry out a test run with the customer to check that the machine is running smoothly overall. This test confirms that any problems have been solved and that the sweeper is operating optimally, with no loss of power or degraded modes.
Common AdBlue system faults :
List of faults: Common faults in the AdBlue system on Bucher Municipal Optifant sweepers include various sensor, pump and ECU communication problems. For example, a faulty fluid level sensor can cause a warning light and error messages, rendering the AdBlue system inoperative and reducing engine power. A faulty AdBlue pump, on the other hand, prevents the correct injection of the additive, which can increase emissions and cause the vehicle to go into degraded mode. A clogged or faulty AdBlue injector causes poor atomization of the additive, reducing the efficiency of the SCR (Selective Catalytic Reduction) system. AdBlue tank heating problems, such as additive crystallization, can block the system, requiring manual intervention. Finally, communication faults between the ECU and DCU can deactivate the AdBlue system, resulting in degraded engine performance.
Common fault codes and their impact: Examples :
SPN521011 FMI1: This fault code indicates a communication problem between AdBlue system modules. When it occurs, the motor may experience a reduction in torque, resulting in a significant loss of power. This torque reduction can render the machine unusable for certain tasks, requiring immediate intervention to avoid prolonged downtime. Diagnosis of this code requires specific diagnostic tools to check connections and communication between the various ECUs.
SPN521010 FMI31: This fault code signals a critical error in the AdBlue system, often linked to pump failure or a blocked injector. The vehicle goes into a degraded mode to protect the engine, limiting its performance and use. Once this code has been detected, it is crucial to check and replace the faulty components to restore normal operation of the AdBlue system and engine.
SPN521003 FMI2: This code indicates an anomaly in the AdBlue dosing system. Symptoms include warning messages on the dashboard and possible non-compliance with emissions standards. To resolve this problem, it is necessary to check the AdBlue injector and pump to ensure that they are operating correctly and that there are no blockages or failures.
SPN521002 FMI2: This fault code relates to the AdBlue tank heating system. When the heater is not working properly, AdBlue can crystallize, blocking the system and reducing the efficiency of the emissions treatment. Solving this problem often involves checking the heating system and manually defrosting the tank if necessary.
Our expertise enables us to work on all JCB engine-powered machines, including all engines and ECUs. You can find out more about the work we've already carried out here.
