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Old 07-12-2011, 05:12 PM
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Join Date: Mar 2009
Location: Philadelphia
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Quote:
Originally Posted by ah-kay View Post
It is a piece of cakee to wire radio.

Measure the old wires with a DMM

1) 1 wire is constant 12V to remember radio setting with key is off
2) 1 wire is switched 12V when key is in posn 2 to turn radio on
3) 1 wire is switched variable 12V when parking light is on for dimming. It may not exist with old cars.
4) 1 wire is ground, probably brown as MBZ uses brown color.
5) 1 wire activare the antenna.
6) Speakers wires.

Once you identify all these wires then you should be able to hook up the new radio.
X2, a simple DMM or even a $2 test light will be your best friend. I keep a test light and DMM in my audio toolbox at all times becuase once the wires are all cut and disconnected its a heck of a time figuring it all out. IIRC (this is totally off the top of my head):
- Brown is ground in MB (always)
- Red is constant 12V
- black with yellow is Acc power (these two might be switched)
In my MBs I've cut into the cigarette lighter circuit since its got all the connections right there. The 4-prong plug from the original Becker radio should have all the connections as well.
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