Mercedes SLK R171 Control Unit Module DC UHI MOST A2118701885

Mercedes SLK R171 Control Unit Module DC UHI MOST is a specialized component from the Electronic control modules and drivers category, designed for integrating connectivity systems in Mercedes vehicles. The module operates within the MOST architecture, ensuring stable communication with the factory multimedia and telephone system, which allows for convenient use of Bluetooth functions in the cabin.

Specifications and technical data

• SKU: A2118701885-1
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2118701885
• Substitutable numbers: A2118701885, A 211 870 18 85
• Location on the vehicle: Front, Right
• Category: ECUs & Computer Modules

Purpose and function of the Bluetooth module

The presented module is responsible for handling the Bluetooth interface in the UHI MOST system, used in Mercedes models, including the SLK R171 series. Its task is to facilitate data transmission between a mobile device and the vehicle's multimedia installation, while maintaining high-quality voice connections and stable operation within the MOST fiber-optic network.

Its location in the front, right part of the vehicle promotes optimal wiring harness routing and integration with other comfort and infotainment controllers. As a result, the module works in tandem with other control units, creating a cohesive communication system within the car.

Construction and integration with the MOST installation

The Bluetooth module has been designed as an element of the MOST bus system, meaning it operates in a digital data exchange network between controllers responsible for audio, telephone, navigation, and other comfort functions. This architecture allows for:

• precise synchronization with the multimedia system's head unit,
• reduction of interference thanks to transmission in the MOST standard,
• easier diagnostics within factory service procedures.

Thanks to a design compliant with the manufacturer's requirements, the module maintains full compatibility with the factory electrical installation, which facilitates installation and subsequent service maintenance.

Application in service practice

Replacing the Bluetooth module is a typical solution in cases of problems with phone pairing, dropped calls, or the system failing to respond to hands-free functions. Using an original component from the Electronic control modules and drivers group allows for restoring proper system operation without the need for interfering with wiring or modifying software beyond standard adaptation.

This type of component is particularly useful for:

• diagnosing faults in the area of MOST communication,
• professional repair of the multimedia system in a Mercedes SLK R171,
• restoring full functionality of the factory telephone set.

Product characteristics and condition

The offered module belongs to the group of used components, which is a typical solution for specialized electronic controllers for premium class vehicles. Such parts are frequently used in professional workshops specializing in automotive electronics because they allow for economical repair while maintaining compliance with the vehicle's factory architecture.

The location of the module in the front, right part of the car facilitates service access while ensuring appropriate operating conditions in terms of temperature and protection against vibrations. This allows the module to work stably with other controllers responsible for comfort and multimedia.

Technical support and knowledge about electronic modules

If you want to expand your knowledge on the diagnostics and repair of advanced multimedia systems and controllers in premium cars, it is worth checking out materials regarding similar solutions in other brands. A good point of reference is an article describing work with iDrive modules and controllers in BMW vehicles – you can find it here: guide to iDrive systems and BMW electronic modules.

In the case of older models, where the availability of new controllers is limited, proven parts from dismantling are a practical solution. This issue has been discussed more broadly in the material: how to use parts from dismantling when repairing older cars, where the technical and economic benefits of such an approach are described.

Related Mercedes Electronic control modules and drivers

If you are planning a comprehensive repair or modernization of the comfort and multimedia electronics area in your Mercedes and need other elements from the same group, such as comfort controllers, body modules, or multimedia units, check the available parts in the Mercedes Electronic control modules and drivers category.