Mercedes D2B Fibre optic connectors

V1.0 29th January 2007

Certain Mercedes cars use D2B fibre optic systems for the Audio system components. Those systems include COMAND, Audio 10, Audio 30, Audio-30-APS, phone systems, linguatronic voice recognition, teleaid and the Digital Bose amplifier.

Note that in later cars (after the W211 E class), the technology changes to MOST bus, those parts are not covered in this document.

The D2B bus is a fibre optic ring, so if any device on it is disconnected or fails, the ring is broken and the system does not work.

In addition to the fibre optic ring there is an electrical 'wake-up' signal which causes the devices on the fibre optic bus to wake up their electronics - without this the devices would all need their fibre-optic electronic circuits powered up all the time which would drain the battery.

Each section of fibre is orange coloured and has a red plastic lens on one end and a white lens on the other. Those lenses/fibres clip into plastic connectors which then plug into the items on the bus.

The Wakeup cables are just all joined together, on many vehicles they are spliced together, on certains ranges they all connect to a multi-way connector called the Wakeup distributor. The wakeup cables are all blue/black coloured.

This document contains the part numbers for some of the connectors

There are two types of plugs, one right angle (which consists of 2 parts), and one that is straight through.

The part numbers are as follows: -
A036 545 08 28 (90 degree connector top part)
A036 545 09 28 (90 degree connector bottom part)
A036 545 07 28 (straight connector).

Sometimes it is necessary to connect two fibres together (a red lens and a white lens will connect together), there is a splice connector for that: -
A000 545 33 84 (D2B splice connector)

Individual sections of D2B fibre can be ordered which come preterminated with a red lens at one end, and a white at the other.

These are ordered as follows: -
A000 540 38 08 XXXX (D2B single fibre)
The XXXX needs to replaced by the length in millimemters. Lengths that I have seen available are 0230, 0430, 0445, 0505, 0530, 0590, 0610, 0755, 0785, 0810, 0880, 1155, 1290, 1390, 1430, 1550, 1880, 2390, 2500, 2640, 2700, 2900, 3080, 3285, 3510, 3630, 4060, 4340, 4440, 4580, 4810, 4910, 5000, 5140, 5370, 5595.