What is it?

The CDC Bluetooth module is a physical electronic device that connects to radio units supporting the CDC interface. The module enables the user to play audio and make calls via Bluetooth. Additionally, the audio could be played via an AUX cable.

The module enables audio playback by emulating the CD changer's CDC interface communication. That is why it works only in the radio unit's "CD" mode, where available CDs, track numbers, minutes, and seconds are displayed.

Features

Main feature list:

• CDC communication with the radio unit - emulating a CD changer and capturing button presses on the radio unit respectively.
• BT control (play, pause, skip, answer, etc.) based on button press events;
• Audio output to the radio unit from either BT or AUX cable;
• Hands-free call control via button presses on the radio unit;
• High quality DirectPath™ DAC PCM5100A for audio output;
• Qualcomm aptX Bluetooth chipset;
• The adapter is automatically recognised as a CD changer.

Installation

Firstly, the user should turn off the radio unit and unplug all the power cables. Secondly, the user must connect the CDC BT module to the radio unit. In CDC radio units, there are at least two CDC interface connector variants available: Mini ISO and 12-pin Quadlock.

Follow the installation instructions in the sections below depending on the connector type.

Mini ISO

For the CDC radio units that have a pinout similar to the one shown in the photo below:

Example of mini ISO pinout sticker on CD unit

The Mini ISO connector (photo below) option of the CDC BT module should be ordered.

Mini ISO connector

Connect the Mini ISO connector of the CDC BT module to the radio unit socket marked in red in the picture below.

Where to connect Mini ISO connector

Additionally, screw in the ground cable to the metallic frame of the radio unit. Any bolt that is already screwed in and is an original part of the radio unit that could be used in this case.

12-Pin Quadlock

Subsequently, for CDC radio units of the connector with the pinout picture below:

Example of 12-Pin Quadlock sticker on CD unit

The 12-pin Quadlock connector (photo below) option of the CDC BT module should be ordered.

12-pin Quadlock connector

Connect the 12-pin Quadlock connector of the CDC BT module to the radio unit socket marked in red in the picture below.

Where to connect 12-pin Quadlock connector

Additionally, screw in the ground cable to the metallic frame of the radio unit. Any bolt that is already screwed in and is an original part of the radio unit that could be used in this case.

Supported Radio Units

Here is a list of supported radio units:

Audi:

• Chorus 2/2+/3;
• Concert 1/2/2+/3;
• Symphony 1/2/2+/3;
• BNS 5.0;
• Navi Plus RNS-E/RNS-D.

Volkswagen:

• Delta (6/7);
• Gamma 5;
• Premium 5/6/7;
• MCD;
• MFD1/2;
• RCD-200/210/300/310/500;
• RNS-300/310/510;
• Blaupunkt R100.

Skoda:

• Beat;
• Dance;
• DX/MFD1;
• Melody;
• MS303/501/502;
• Nexus
• Rhapsody;
• SatCompass;
• Stream;
• Swing;
• Symphony;
• Symphony CD;
• Gamma.

Seat:

• Adagio Concert 2+;
• Alana;
• Aura;
• Elba;
• Lena;
• Liceo;
• MCD;
• MFD1;
• Odeon;
• Scala;
• SE359/360;

Usage

Interface

Once the CDC Bluetooth Module has been installed to work with the radio unit, power it on and enter "CD" mode by pressing the "CD" button. The "CD" mode must be used if the user intends to play audio via the CDC BT module. The user can select whether to play the audio via Bluetooth or the AUX cable.

Note: Make sure to disable "mix" or "random" mode on the radio unit to improve button press detection and get rid of RANDOM text or MIX icon on the radio display. It may be done by going to the settings via MENU or similar buttons.

Bluetooth Pairing

Once the CDC Bluetooth Module has been installed to work with the radio unit, to play via Bluetooth, the user should connect the cellphone (or other BT device) to the CDC BT module. If no BT device is connected, the CDC BT module will be in pairing mode automatically. When there is no device connected, the radio should display TRACK 80. Once a BT device is connected, the radio unit displays TRACK 01.

If there is a BT device already connected to the CDC BT module, for another device to be connected, the pairing mode could be entered with the following three-button press sequence: CD5 -> CD5 -> CD5 or << -> << -> << (x3 seek backwards). After this, the radio unit displays TRACK 50 and the CDC BT module will be able to connect to the new device. If there was no BT device connected, the radio unit would still display TRACK 80.

To reset the list of devices paired with the CDC BT module, enter the following three-button press sequence: CD6 -> CD6 -> CD6 or >> -> >> -> >> (x3 seek forwards). After this, the radio unit displays TRACK 60 and the CDC BT module will not have any BT device to connect to because the list of paired devices has been cleared. Once the reset paired list command takes effect, the radio unit will display TRACK 80.

Once a BT device is paired with the CDC BT module, it will try to connect to the device automatically during the power-on of the radio unit.

Selecting Between Bluetooth and AUX

The CDC BT module allows switching between Bluetooth and AUX for audio input. The selection between AUX and BT is determined by the physical connection of AUX cable and the CD3 button press. For older Audi Concert radio units, user must increment (or decrement) CD number up to CD3 for the audio source selection to be triggered. If the AUX cable is disconnected or there is a call happening over a connected BT device, BT will be selected as the audio source automatically. BT is also selected on the CD3 button press even when AUX is connected and has been selected as the audio source. To select AUX, the cable must be connected (even if the other end of the cable is not connected to an AUX device) and button CD3 pressed to toggle audio source from BT to AUX.

When AUX is active, the radio unit displays TRACK 10. When BT is selected as the audio source, the radio unit updates to display TRACK 1. However, after BT selection, track number might be changed with track skip buttons and other actions.

Audio (Music) Control

When a device is connected via Bluetooth, it is possible to control the music (audio track) by skipping forward, backward, playing, and pausing. Respectively, this may be done with the right arrow, left arrow, and CD1 (for both play and pause) buttons on the radio unit. If there is no CD1 button, the user may use "next CD" and "previous CD" buttons to change CD number to CD1 (from CD6 or CD2) to play/pause the audio.

Also, note that the CDC BT module will try to play the audio on a connected device after the radio power-on. However, the connected BT device should have some audio track available for this to work. For example, there should be a YouTube video open on the phone.

Call Control

When a device is connected via Bluetooth, it is possible to perform general call control. An incoming call will be answered by pressing the right arrow, rejected with the left arrow, and the last number redialed by entering the following three button press sequence: CD2 -> CD2 -> CD2. If there is no CD2 button, the redial command does not work. Also, in order to redial, audio playing via BT must be paused.

Note: the CDC BT module comes with a microphone, which would be used during calls.

When the AUX cable is selected for audio input, but the module remains connected to the phone via BT, calls may still be answered. The CDC BT module automatically switches the audio source back to BT when it detects an incoming call.

Miscellaneous Control

To reset the track number to 1, minutes and seconds to 0, press the button CD4 (or increment CD number to CD4).