BMW X3 F25 X4 F26 X5 F15 Engine ECU Kit CAS4 30dX N57N 258HP Key Automatic

BMW X3 F25 X4 F26 X5 F15 Engine ECU Kit CAS4 30dX N57N 258HP Key Automatic is a complete, used electronic package designed for BMW vehicles with a diesel engine and automatic transmission. The kit includes the engine control unit (ECU), the CAS4 module, and a key, which facilitates a consistent configuration of the powertrain and authorization system. This solution allows for a technically correct replacement of the control electronics within the powertrain and the vehicle start system.

Specifications and technical data

• SKU: 8586540-9
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8586540
• Substitutable numbers: 13618586540, 8586540, 13618572440, 8572440, 13618573789, 8573789, 13618574373, 8574373, 13618518172, 8518172, 13618574238, 8574238, 13618572002, 8572002, 0281031950, 0 281 031 950, 61356824383, 6824383, KZ, 9367367
• Fuel type: Diesel
• Gearbox type: Automatic
• Category: ECUs & Computer Modules

Purpose and compatibility

The presented kit is part of the Electronic control modules and ECUs group, dedicated to BMW X3 F25, X4 F26, and X5 F15 models with the 30dX N57N 258HP engine. Integrating the engine controller with the CAS4 module and the key ensures immobilizer data consistency, which is crucial when replacing electronics in vehicles with advanced security systems. The system is prepared for use with a Diesel engine and an automatic transmission, which reduces the risk of communication issues between the engine controller, the transmission module, and other vehicle systems.

Construction of the ECU CAS4 kit with key

The kit includes an engine ECU responsible for precise management of the powertrain, a CAS4 module performing authorization, starting, and key handling functions, and the key itself matched to this set. Such a configuration facilitates adaptation in the vehicle because the key components communicate on a common database, which minimizes the need for deep programming intervention. Combining the ECU and CAS4 in one package is particularly beneficial when replacing a damaged engine controller or dealing with start/stop system issues, where maintaining coding consistency and immobilizer synchronization is required.

Application in the powertrain

In BMW vehicles with the N57N diesel engine, the engine controller is responsible for controlling injection, turbocharging, auxiliary equipment operation, and cooperation with the automatic transmission. The CAS4 module oversees key authorization, comfort functions related to starting the vehicle, and data exchange with other body modules. Thanks to this, the BMW X3 F25 X4 F26 X5 F15 Engine ECU Kit CAS4 30dX N57N 258HP Key Automatic constitutes a coherent solution for the powertrain and security system. A set configured in this way is particularly useful for repairs after electronic failure, starting problems, or damage resulting from flooding or electrical surges in the wiring harness.

Benefits of using a used OEM kit

A used kit sourced from a dismantled BMW vehicle retains its factory characteristics, which promotes proper cooperation with other modules in the car. Using original components from the same engine and transmission family increases the chance of seamless integration with the vehicle's communication bus. For workshops specializing in the BMW brand, such a set is a practical solution for advanced electronic repairs, as it limits the number of variables during diagnostics and programming. The consistency of the engine controller, CAS4 module, and key allows for shorter configuration times and reduces the risk of conflicts in the security system.

Technical support and additional resources

If you want to better understand the operating principles of BMW engine controllers, comfort modules, and the iDrive system, and learn practical tips on using parts from dismantling, it is worth checking out our guide: Driving pleasure for years – how to take care of iDrive systems and electronic modules in BMW 3 and 5 series models using parts from dismantling?. The article discusses typical repair scenarios and can also be helpful when working with modules related to the presented kit. If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other elements from the same group, such as engine controllers, comfort modules, or powertrain management systems, check out the available parts in the BMW Electronic control modules and ECUs category.