In this post I’ve described in as much details as possible the steps you need to follow to retrofit an original Audi Bluetooth module into your Audi A6 4F.
You will need the following parts for the retrofit
The bluetooth module that you should look for is with part number 4E0 910 336 MX. Don’t buy old modules since they’re known to be often faulty and are replaced by Audi.
The optical cable that you need looks like the one on the photo below. You can purchase any optical cable splitter (for AMI for example) or if you have access to a second-hand car dealership to get the necessary cable from there:
Here’s a schematic how to connect the optical cables in the MOST optical circle.
You can get the other cable either from Kufatec or from a second-hand car parts dealership. Note that it’s a bit hard to separate only the Bluetooth cable from the rest of the installation. However’ once you have it, it’s simply a matter of connecting three cables with the same colour.
The same colours go out of the CD Changer, you simply need to attach those together.
Microphone cable & Microphone
Finally, you need to connect the microphone that’s under the plastic with the reading lights above your head. This cable goes through the right pillar. Don’t remove anything, the cable can be tucked under the trims. Here’s how the end of the cable looks like.
The microphone part number is 4L1 035 711 B and it looks like this:
When installed in the factory, the Bluetooth module is placed under the driver’s seat. This is not the best position to add it when you’r retrofitting it though. In addition, there have been complaints about water getting under the seat shortcutting the module.
It’s much easier to install it behind the glove department. It’s right next to the CD changer and/or AMI unit. Note that in the optical circle, the BT unit has to be last, before the amplifier. This means that you need to connect it AFTER the last device in the glove department – CD Changer or AMI.
There’s plenty of space there, and if you don’t have the module to automatically adjust your headlights, there’s even a module niche that’s with the perfect size for the module.
First, you need to open the CAN Gateway adaptation. In VCDS, there is a helper that allows you to place checks to the functions you want to add. Place a check on the “Telephone” system. You will now have another module that you can configure. Finally, you need to restart the MMI system. To do this open the Control Head unit, go to Adaptation, add 1 to channel 111 and press the Test button. That will restart the entire MMI system. That’s pretty much it! You can now use the Tel button on your MMI control unit, configure and pair devices to your Bluetooth module.