Mercedes-Benz Forum banner
1 - 5 of 5 Posts

· Registered
2003 Mercedes E320
94 Posts
Discussion Starter · #1 ·
96 Mercedes E320.
problems continue with this car. Recently the volume button on my car's radio is not working and the quality of original stereo unit is crappy.

I ordered an aftermarket stereo from groupon for a good price.

Questions I have for you is can i connect the wires directly without an adapter. can someone help me with color of wiring on the connector and tell me what each wire is for such as memory, power, speakers. I can just strip with wire and connect to the new head unit. I can't find adapters for his car on line unless someone can help me.


· Registered
1999 E320 Wagon
368 Posts
+1 on Crutchfield
You will need an adapter pigtail that plugs into the car side. You will have to solder this to the pigtail connector that comes with the after-market radio. Use heat shrink instead of electrical tape.

· Registered
2000 E320 4-Matic Wagon
29 Posts
I have a similar radio installation question. I bought a new no-name Android-based stereo for my W210 where the radio comes with a wiring harness. The end of the wiring harness that is not connected to the radio is a standard female ISO connector (in other words, the radio came with a wiring harness, one end of which connects to the radio, the other end of which has a female ISO connector). Our W210's radio wiring harness is a standard male ISO connector. In a perfect world, I'd just plug these two ISO connectors together and the radio would work. That appears to not be the case as the radio appears to be receiving no power (neither when the car engine is turned on, nor when the key is just in the ACC position).

I've confirmed, by re-attaching the old becker radio, that the W210's wiring harness is still carrying power and therefore, I haven't blown the car's fuse for the radio circuit, I think.

So, please give me some advice. Am I supposed to buy a female ISO connector to attach to the stock W210 wiring harness and then buy one of the Metra harnesses that contains a male ISO end to hook to the female ISO connector provided with the radio AND swap some of the wires in my "wiring bridge" between the W210's harness and the harness provided with the radio?

If you can't tell...I'm new to aftermarket radio installations.

The W210's male ISO connector consists of two sections: the "A" section and the "B" section. The "A" section consists of all of the speaker wires and those wires seem to line up correctly with the speaker wires on the female ISO connector attached to the new radio.

I have questions about the "B" section - the W210's B wiring, has two rows of pins. According to a wiring diagram found on this forum there are eight pins laid out like below:

"1 3 5 7"
"2 4 6 8"

pin 1 has no wire connected, but the wiring diagram has it listed as "speed dependent volume control". Pin 2 has a grey wire, the wiring diagram lists it as "not used". Pin 3 has a yellow/Blue wire and is label on the diagram as "Phone Mute", Pin 4 is Red/White, labelled as "Constant 12V". Pin 5 is Blue and labelled as "Power Antenna". Pin 6 has no wire and is labelled as "N/A", Pin 7 is empty, and Pin 8 is Brown and is supposed to be the Ground.

Now, I am confused. How is it possible that the W210 wiring harness has nothing labelled as "12v when key is in ACC mode"? I don't expect the harness to just have a constant 12V and a ground.

On the female ISO wiring harness attached to the radio, the Pin 4 for constant 12V matches up with the W210 harness, the Pin 8 matches up for Ground. Pin 6 is labelled as "Illumination", which is unpopulated on the W210 harness. Pin 7 on the radio's harness is labelled as "ACC", which seems to be empty on the W210's harness. The radio's harness is empty on Pins 1, 2, 3, and 5. The new radio has a separate antenna connection to which I can attach the W210's separate antenna wire with an adapter, so I'm not worried about the radio having PIN 5 empty. I don't know what Pin 2 on the W210's harness is supposed to be for. That is the one with the thin grey wire attached. I'm also not concerned about PIN 3 being depopulated as I won't be using the W210's built in phone system.

So, please, help an audio newbie out. When I plug the W210's male plug into the new radio's female plug, I expected the radio to at least turn on when I turned on the car, given that the constant 12V and the ground wires lined up between the two harnesses. I need help convincing myself that the radio itself has no problem, then I need help convincing myself of the proper way to wire it. Any help is appreciated.

If anyone is interested, the new stereo is this Eonon double din unit - Eonon G2110 | Car GPS | Car DVD GPS | 2 Din Car GPS DVD | Android Car GPS | Android Car DVD Player

· Registered
2001 E320 Wagon
85 Posts

I had to grab ACC power from the cigarette lighter. I know it seems strange but I just did this install. Did a couple of searches and found out just as you did no ACC power in the harness. All the posts say grab power from cigarette lighter.

Now on to other important info. Does your wagon have the factory amplifier? Because if you do you should use it.

For my 2001 wagon I have the factory amplifier installed. I dont have the "Bose" system everybody mentions but I do have an amp that sits right next to the CD changer in the pass rear trunk.

I am using that factory amp with this stereo

And it sounds great! but to do this you must get a stereo with 4v pre-outs. Alot of stereos have 2v preouts.

I could not see on the link you sent what the power of the pre-outs are on that stereo for some reason they left it off the specs.

to do this you use this harness and plug the supplied rca cables to the pre-out on your new stereo.

the Blue wire labeled "power antenna" needed to go to my new stereos harness blue wire labeled "remote on" to turn the amp on.

Great video on how to take apart dash to get to power from cigarette lighter....

hope this helps.

1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.