BMW E81 E82 E87 LCI E88 N47S 123d ECU Kit DDE 7812502 + CAS3 + Key Manual

Visual condition of the part

The product shows signs of use visible in the photos.

BMW E81 E82 E87 LCI E88 N47S 123d ECU Kit DDE + CAS3 + Key Manual is a complete control set designed for BMW 1 Series models with the N47S 123d engine, equipped with a manual transmission. The set includes the DDE engine control unit, the CAS3 module, and a matched key, which facilitates professional replacement of drivetrain electronics without the need for tedious programming from scratch. This is a practical solution for workshops and users who want to restore full functionality to the engine control system in a consistent and technically correct manner.

Specifications and technical data

• SKU: 7812502-3
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7812502
• Substitutable numbers: 13617811702, 7811702, 13618512589, 8512589, 13617812002 13617810002 13617808402 13618506325, 7812002 7810002 7808402 8506325, 13617809002 13617812502 13618508713, 7809002 7812502 8508713, 0281015553, 0 281 015 553
• Gearbox type: Manual
• Category: ECUs & Computer Modules

Purpose and compatibility

The presented ECU DDE kit with CAS3 and key has been prepared for BMW 1 Series cars of the E81, E82, E87 LCI, and E88 generations with the N47S 123d unit and manual transmission. Combining the engine controller with the CAS3 module and the key allows for maintaining the consistency of the immobilizer system and starting logic, which significantly simplifies the installation process compared to replacing individual components.

A solution of this type is particularly useful for repairs following electronic damage, communication problems between controllers, or when it is necessary to replace the entire set due to a failure of the drivetrain control system.

Structure of the ECU DDE + CAS3 + Key kit

The set includes three key elements responsible for engine management and starting authorization:

• the DDE engine control unit responsible for processing sensor signals and controlling the operation of the power unit,
• the CAS3 module, which handles security functions, key authorization, and start/stop logic,
• a key matched to the set, ensuring correct cooperation with the CAS3 and DDE.

Thanks to this, you receive a consistent set that can be adapted to the vehicle after proper configuration, in accordance with procedures used in services specializing in BMW electronics.

Application in service practice

Replacing the complete ECU DDE kit with CAS3 and key is often chosen in situations where repairing a single module is unprofitable or carries a high risk of recurring failure. From a workshop perspective, this means:

• the ability to efficiently restore the functionality of the engine control system,
• reducing diagnostic time related to controller incompatibility,
• easier adaptation compared to selecting random, unpaired components.

For the end user, this means a more predictable repair result and a greater chance of stable drivetrain operation after replacing the electronics.

Characteristics of the used product

The offered set comes from dismantling and has the status of a used electronic module. Such components are frequently used in professional workshops because they allow for a significant reduction in repair costs while maintaining the manufacturer's original specifications. In the case of engine control electronics, this is particularly important, as maintaining the factory system architecture affects the stability of the power unit and the correctness of communication with other modules in the vehicle.

Expert support and additional information

If you want to better understand how to use used engine controllers, comfort modules, or multimedia systems in BMW cars, it is worth reaching for expert materials. Practical tips on repairing the iDrive system, FRM modules, and engine controllers using parts from dismantling can be found in the article 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?, which helps organize knowledge about working with BMW electronics.

If you are planning a comprehensive repair or upgrade of the engine control area in your BMW and need other elements from the same group, such as additional controllers, auxiliary modules, or drivetrain management systems, check the available parts in the category Electronic control modules and controllers BMW.