MsPauly, you're pretty much all over the place with multiple posts basically getting at the same set of questions. I am happy you're reading and researching, and trying to understand - that's a good thing, and many folks don't do it, unfortunately. But we could probably answer your questions more thoroughly (and more coherently for you) if they were gathered in the same string.
The D2B is Digital Data Bus (sometimes called the Domestic Data Bus), a fiber optics bus (circuit with at least several components operating on it) that was proprietary to Mercedes. Only Mercedes, Jaguar, and some Volkswagen models used it.
Fiber optics "wiring" differs from copper wiring in that fiber optics leads ("wires") are comprised of glass or polymer (plastic) fibers that conduct light, whereas regular wiring uses metal - most often, copper - to conduct electricity. A fiber optics system will use devices that convert electrical signals to modulated light; and with different modulations, or coding, for each device, multiple devices can use the same "wire."
The D2B Bus was succeeded by the MOST (Media-Oriented Systems Transport) fiber optics bus beginning with Model Year '04 (later in some models). MOST is a more capable bus, and rather than being proprietary, is an automotive industry standard used by many manufacturers. You cannot use equipment designed for one type of bus with the other.
The equipment on the fiber optic busses would include COMAND and navigation systems, Audio 10, 20, 30, and 50 units (used where the car lacks COMAND), cell phone, CD changer, satellite radio, voice control - basically anything connected to or playing through your audio system.
There are also other busses in the car; CAN (Controller Area Network) busses also exist - CAN B is the interior bus; CAN C is for the engine; and CAN D is the diagnostics bus. These are copper wire electronics busses, and they communicate with each other and with the fiber optics bus when necessary through devices called "gateways." In simplest terms, CAN busses help various sensors and displays operate; and with the help of "SAM" units (Signal Acquisition Modules), they communicate the fact that you operated a control (for example, a button or a lever) to the components that must operate in order to carry out the button's function. But we don't need to discuss them extensively here - I mention them just so that someone can't throw you off the track when you need information on your D2B bus or its electronics.
OMG! (which stands for Oh My Goodness!) I can not thank you enough for all of your help!!
I am sorry for all of the jumping around on different threads but my first couple of posts resulted in absolutely NO answers so I was just trying to put as posts out there as possible to get as many replies as I could. I figured the more people I talked to the better I could understand this.
I completely appreciate your thread on your install of the Denison. WOW that was a lot of detail!
My other vehicles are a 93' Tahoe and a '79 Eldorado which I work on from time to time if the job is small. But I have not ever attempted anything electrical in either one - Aside from replacing an alternator - but that seems WAY easier than what I am about to embark on with my MB.
Surprisingly, my '79 Eldo used fiber optics in some of the lighting. My jaw hit the ground the day I stumbled across that. Who would have thought they were putting fiber optics in cars in the seventies! I was shocked!
Anyway - thank you so much for all of your patience and lengthy explanations. You are my new best friend!!
I'm a better friend than you know - because you completed your information under the avatar, I know you are located near one of the best design teams/installers for Mercedes electronics anywhere - Mid-City Engineering in Chicago, with forum member Rob13572468 in residence. Believe me, they can take care of any of your MB electronics needs - in fact, they design and install equipment to do things MB never thought of! See the response to your question in the string at http://www.benzworld.org/forums/aud...y-500-most-not-ready-prime-8.html#post3350708 for more info. They can sell you a Gateway 500, install it, and be sure you know how to use it - and they will provide follow-up, as Rob has done often here on the forums.
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