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Audio Systems/Motorola Vibrasonic model KM202R


QUESTION: This model has the on/off and speaker fade controls built into the face of the unit. My question is regarding the wiring. I have no schematic to install the unit and would like help on identifying the wires. There are 7 wires in total. At the left rear of the unit there is a pair of gray wires and a pair of brown wires. I think those are the front and rear speaker wires, but I don't know which pair goes to which speaker. Next, it has a single black wire coming out of the center of the left side of the unit. It is the largest gauge wire on the unit.I think that is 12v in.  Finally, there is a pair of wires coming out of the right side of the unit. One wire is black and the other is green. I think those may attach to the speaker outputs from the radio, but if they do I don't know what to do with the speaker common wire from the radio. Thank you very much.

ANSWER: You might try reading through this web page looking for one of the respondents that could send you the wiring diagram.

I don't have a wiring diagram and could not find one on the internet.

But you can maybe figure it out by yourself.  If you open the unit up so you can see where the wires go inside it may provide you with the necessary information.

The unit uses 12v to power the transducer.  The transducer is connected to one end of the spring.  The other end of the spring is the audio output.  With 7 wires I suspect two are for audio input to the transducer coil; two more are for the audio output; two more are for the power in one being the 12v line the other ground; the 7th wire may be for chassis ground or it could something else.

Hope this helps.

---------- FOLLOW-UP ----------

QUESTION: Thank you very much ! I opened it up and some of the wiring became clear. The pair of brown wires and the pair of gray wires are attached to the fader switch, so they are speaker wires. One wire in each pair has a white tracer on it. The single black is attached to a wire coil and from there goes to the on/off switch as a heavier red wire and attaches to the top row of terminals on the switch. One of the two remaining wire is soldered to the inside of the case. The last wire goes to the center position of the lower row of terminals of the on off switch. I took a good picture of the inside, but do not know how to attach it. I would like to send the picture and get your input again when I can get someone to help me load it. I really appreciate the help !

Thanks. Uploading a picture can be done with a followup and just follow the link at the bottom of the question box.  Of course you must have the picture on the pc first.

Or, if you want you can email it directly to me at this email: (replacing the # with @).  

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Audio Design Engineer; systems, loudspeakers, cd/dvd players, etc. I am knowledgeable in all high end audio equipment and installations. MAKE SURE YOU GIVE A MAKE AND MODEL NUMBER AND CAR IF IT IS AN AUTO QUESTION. Note: I am getting some who ask good questions that take a lot of time to research but then the questioner fails to read the answer. Please don't ask questions unless you are seriously looking for an answer. If you find an answer to your question otherwise then let me know with your reply. Thank you.


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