BMW E81 E87 LCI E90 118d 318d N47 Diesel ECU KIT DDE 7811701 CAS3 + Key Manual

BMW E81 E87 LCI E90 118d 318d N47 Diesel ECU KIT DDE 7811701 CAS3 + Key Manual is an original electronic control module designed for BMW 1 and 3 series diesel engines paired with a manual transmission. This used, fully functional ECU ensures precise management of the diesel engine, stable communication with the vehicle's electrical system, and the possibility of professional repair or replacement of the factory engine computer. By maintaining OEM specifications, this is a particularly attractive solution for workshops specializing in the BMW brand and informed users looking for a proven engine control unit.

Specifications and technical data

• SKU: 7811701-3
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7811701
• Substitutable numbers: 13617809001, 7809001, 0281015042, 61359147220, 9147220, 13618506281, 8506281, 13617812501136178100011361781170113617807143, 7812501781000178117017807143, 13617807204136178120011361780782813617807529, 7807204781200178078287807529, 1361850
• Fuel type: Diesel
• Gearbox type: Manual
• ECU type: Engine Control Unit
• Category: ECUs & Computer Modules

Purpose and function of the BMW engine control unit

The presented control unit belongs to the Electronic control modules and ECUs category and plays a key role in managing the powertrain. It is responsible for controlling fuel dosage, injection parameters, engine auxiliary equipment, and communication with other modules in the vehicle. It has been designed for use with diesel engines and manual transmissions, which is important when selecting the appropriate ECU for a specific configuration of the BMW 1 Series (E81, E87 LCI) and 3 Series (E90) in 118d and 318d versions. As an Engine Control Unit, the controller integrates with the vehicle's bus, enabling proper operation of safety systems, OBD diagnostics, and comfort functions dependent on engine operating parameters. Proper selection of the module helps avoid communication issues, control errors, and improper engine performance.

Benefits of using an original BMW ECU

Using an original engine control unit in the BMW E81, E87 LCI, and E90 brings a number of practical benefits, especially in vehicles with a diesel engine and manual transmission:

• preservation of factory engine control maps and onboard system logic,
• guaranteed compatibility with the electrical installation and other BMW electronic modules,
• easier adaptation and coding compared to low-quality replacements,
• possibility of professional diagnostics using standard BMW service tools. For workshops and users, this means stable engine operation, predictable vehicle behavior, and a reduction in the risk of recurring faults related to engine electronics. Combined with the correct installation and programming procedure, such a controller represents an effective service solution when replacing a damaged ECU.

Application in vehicles with diesel engines and manual transmissions

This engine control unit has been prepared for use with BMW diesel engines, which is important for the correct control of injection, boost pressure, and exhaust gas treatment systems characteristic of diesel engines. Additionally, it is intended for configurations with a manual transmission, ensuring that the torque control logic, gear shift assist functions, and engine safety features are matched to this specific gearbox. In practice, this means that when replacing the ECU in a BMW 118d or 318d with a manual transmission, you can maintain the consistency of the drivetrain operation without the need to interfere with software specific to other types of transmissions. This is important both from the point of view of component durability and driving comfort.

Professional installation, diagnostics, and selection of the control unit

Due to the advanced electronic design and integration with the vehicle's security systems, the installation of an ECU in a BMW should be performed by a workshop with appropriate diagnostic tools and experience in working with electronic modules. In many cases, software matching, coding, or synchronization with the immobilizer is necessary, so it is worth including these steps in your repair plan. To better understand how to use a used engine control unit and other electronic modules in BMW 3 and 5 series, it is worth reading the practical tips contained 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 dismantled parts?. There you will find information regarding the safe use of dismantled parts, including engine control units. If you want to further optimize the process of selecting a used ECU for a specific BMW vehicle, the guide describing the use of the VIN number when choosing premium components will be helpful: How to choose original used parts for BMW, Audi, and Mercedes using the VIN number?. This will minimize the risk of purchasing an unsuitable module.

Related BMW Electronic control modules and ECUs

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 control modules, auxiliary controllers, or additional ECU units, check the available parts in the BMW Electronic control modules and ECUs category.