2021 Audi MIB3 Infotainment System Overview

Introduction to the Audi MIB3 Infotainment System

Audi has introduced the third generation of its modular infotainment matrix, known as MIB3, representing a significant conceptual advancement in vehicle technology. This system incorporates newly externalized functions and advanced transmission methods. The eSelf Study Program 970893 provides a comprehensive overview of the MIB3 generations, its initial implementation across the Audi range, and the underlying offer concepts.

This new system impacts a wide range of 2021 Audi models, including the A3, A4, A5, A6, A7, A8, Q3, Q5, Q7, Q8, and e-tron. Understanding the intricacies of the Audi e-tron MIB3 infotainment system, alongside other models, is crucial for both technicians and owners.

MIB3 System Versions

The MIB3 system was first introduced in 2019 with the product upgrade of the Audi A4 (type 8W). To accommodate various model ranges, Audi utilizes three distinct versions of the MIB3:

• MIB3 Basic
• MIB3 High
• MIB3 Premium

The primary distinction for the J794 control unit in the MIB3 Basic version is the absence of an LVDS connection to the J285 control unit in the dash panel insert. MIB3 Basic is exclusively fitted in modular transverse matrix (MQB) vehicles. For MIB3 High and MIB3 Premium, the J794 control unit can be identified by its white connector, which signifies the LVDS connection to the J285 control unit. The differences between MIB3 High and MIB3 Premium largely stem from software variations and other hardware components within the J794 unit itself.

Key Hardware Components

Control Unit 1 for Information Electronics (J794)

The J794 control unit serves as the central hub for information electronics in the MIB3 system. Unlike its predecessor, the MIB2+, the MIB3's J794 no longer integrates the mobile network module, SD card reader, or SIM card reader. All Audi connect services now operate via an embedded SIM card located in the J949 emergency call module control unit and communication unit.

The J794 unit provides two USB connections for media playback. A MOST bus connection is only present in certain models equipped with optional features such as a TV tuner, Audi virtual cockpit, or Head-up display. Different hardware versions of the J794 are utilized depending on the specific vehicle model and platform (MQB or MLB).

Emergency Call Module Control Unit and Communication Unit (J949)

The J949 unit plays a critical role as both a GPS receiver and a mobile network receiver. Mobile network antennas are connected directly to the J949, which then transmits data to the J794 via Ethernet. In MLB vehicles, Wi-Fi and Bluetooth antennas are also connected to the J949, whereas in MQB vehicles, these antennas connect to the J794.

The J949 unit comes in two main versions: the connectivity box and the OCU (Online Connectivity Unit). Both versions offer LTE-capable mobile network modules, multiple LTE antenna connections, a GPS module for location services, an integrated backup antenna, and an emergency battery. The OCU version, specifically OCU3, is fitted in the Audi A3 (type 8Y) and has an even more significant role in vehicle connectivity. Diagnosis for the J949 is performed using address word 0075 - Emergency call module.

Digital Sound Package Control Unit (J525)

The J525 unit is responsible for actuating the loudspeakers within the MIB3 system. A notable change from previous generations is the use of the Automotive Audio Bus (A2B) for audio transmission, replacing the MOST bus. The J794 control unit acts as the master for the sound system, handling functions such as up to eight channels, up to 180W output, sound processing, audio signal processing, volume control, and sound adjustment (VNC and ANC).

Two types of J525 units are used: one for the Bang & Olufsen Premium Sound System with 3D sound and another for the Bang & Olufsen Advanced Sound System with 3D sound (8RF). Active Noise Cancellation (ANC) functionality, when present, utilizes four microphones connected to the J525, with signals transmitted via A2B to the J794 for processing.

MMI Display (J685, J1060)

The MMI display in MIB3 systems features multi-touch capability, acoustic feedback, and, in C-series and D-series models, haptic feedback with pressure sensors. The displays offer high resolution and up to 900 candela brightness. Different display sizes are available:

• 8.8-inch MMI display (J685): Features 1280x720 pixels and a 194x109 mm active area, typically showing 6 tiles on the main menu. If it's the sole display, it indicates an MIB3 Basic system. When combined with a lower display, it can be MIB3 Basic or High.
• 10.1-inch MMI display (J685): Offers 1540x720 pixels and a 233x109 mm active area, displaying 8 tiles on the main menu. As a standalone display, it signifies an MIB3 High system. When paired with a lower display, it indicates an MIB3 Premium system.
• 8.6-inch lower touch display (J1060): With 1280x660 pixels and a 194x100 mm active area, this display primarily controls air conditioner settings.

The MMI displays are controlled by the J794 via the CAN bus, with picture data transmitted via LVDS. For dual-display setups, the J794 sends a