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Aftermarket head unit install while retaining factory amplifier on MOST fiber Benz's!

312K views 382 replies 106 participants last post by  jyl 
#1 · (Edited by Moderator)
**EDIT: Xtrons, who is the manufacturer of the Head unit i chose to go with, now offers complete 'plug and play' kits
for all different Benz models 2003+ with MOST fiberoptics. with the analog to digital fiber converter that is needed, kits run $450 or less. Current head units for sale run android 6.0 or 7.1.**


This last weekend I got around to installing an android 5.1.1 aftermarket head unit for my 2005 E class. Normally, the only way to do this while maintaining decent sound quality would be to completely bypass the fiber optics and install a new amp in the trunk. NOT anymore! AVIN (which just so happens to be a sponsor of benzworld:wink) has a product out for Mercedes vehicles equipped with MOST fiber optics for the audio system, which converts the analog RCA output from the head unit into the MOST digital signal that's sent over fiber! its plug and play from the head unit to the fiber optics plug. Priced at $250, i think this is a fantastic alternative to completely rewiring your cars audio system!

The sound quality is fantastic too, no different than factory from what my young ears can tell.

This install information is specific to my E Class, obviously. But it would extend to any benz equipped with Command and MOST fiber optics between MY's 2003-2011.

Install:

CAUTION!!!!!!!!! BE VERY CAREFUL WITH THE FIBER OPTIC WIRES YOU WILL BE WORKING WITH. DO NOT kink them, they WILL break.

The head unit is bought is : For Mercedes Benz E Class W211 4 Core Android 5 1 DVD GPS 2Din Radio Car Stereo | eBay

The Fiber optics interface for E CLASS is from: https://avinusa.com/most-fiber-optic-amp-interface-for-w211-e-class-mercedes-benz.html
The fiberoptics interface for ML,GL, and R class is from: https://avinusa.com/most-fiber-optic-amp-interface-for-mercedes-ml-gl-r.html

first things first is removing the radio and CD changer. There's plenty of information and videos out there on how to do that.

Next is to wire up ground and 12v constant for both he radio and Avin box. (the AVIN box NEEDS to be connected to constant 12v, NOT a switched source.) ACC is controlled through CAN-B, which ill cover later. now connect the RCA output to the RCA input from the avin box.

NOTE: On the radio i installed, i had to connect the FRONT RCA outputs, not the rears, because for some reason the Phone Bluetooth audio output only came out of the Front RCA output.

Connect the Fiber optic plug into the avin box. I installed the box above the driver side Knee Bolster, that is removed with two screws. I also routed the GPS antenna through there, and up the driver a pillar to the windshield.
The CAN wires need to be run to the CAN-B bridge located under the carpet in the plastic raceway along the drivers side rocker panel. Its a skinny rectangular plastic connector that has tons of Brown and Brown/Red wires running to it. splice on to each one of those wires, and there's your CAN connections. That controls your reverse lead, Radio turn on, steering wheel controls, dimming when headlights are on, and a couple other things i cant remember.

Connect any other optional equipment you want, like reverse camera, ipod, AUX-in, ETC.

Now its time to run the Antenna cable to the trunk! Run that cable under the carpet along the rocker pannel and under the rear seat, and then through to the trunk. you need to connect that to the LARGE antenna wire going into the AMP. remove the amp by removing the 3 10MM bolts holding it in place (its located on the drivers side of the trunk hidden between the fender and false trunk wall, right behind the fuse box.)

There are TWO connections going to/from the Amp with the same connector, disconnect BOTH, and connect the antenna cable you ran to the large diameter cable that you just unplugged from the amp.

Secure the amp back in place, button everything up, and you should be good to go. It was a pretty easy install that i did over the weekend. it could be done in a single day if you busted your butt and had a handy guide like this to help you out. :wink

Here's a video i did with a quick review of the head unit as well as some general install information.
 
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#3 · (Edited)
Yes it is a Compacitive touch screen. its very responsive.

LOUD is a equalizer effect. it just....... makes the music louder. haha. I have it on all the time, its a nice sounding effect.

Those physical buttons are basically all shortcut keys, and you can change them to whatever you want! for instance, i changed the 'mode' button to a shortcut to the music app. I also changed the 'loud back' to just a back button, since the 'loud' setting is toggled ALOT less than using a physical back button. Every key also has a changeable long press setting.
 
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#6 ·
i used scotch locks with some dielectric grease to splice into the can wires, then wrapped them in electrical tape.

And AHH, i knew i missed something.
yes, you will need a 5m antenna cable to stretch form the head unit to the amp. My radio came with an antenna adapter to go from the Benz antenna connector to standard iso male antenna adapter. looks like this:
 
#7 ·
the sd card slot for both music/videos as well as the gps sd card slot is hidden under false buttons on the bottom left of the units buttons. (look at the photo of the unit and you will see what i'm talking about. )

My phone is an android (Nexus 5x), and the screen mirroring works great! not sure how it would work for iphone, but then again i don't see the point of screen mirroring. :grin

the majority of communication between the head unit and your phone is through Bluetooth, so that shouldn't behave any different than with android.
 
#9 ·
Yes you are able to use the factory Mic, but i didnt even bother. The mic that's standard in the aftermarket HU is crystal clear from what ive been told by people i've called. Works great for voice recognition as well. my radio included an adapter to plug into the factory mic.
 
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#10 ·
Great information! So your solution is not head-unit dependent, correct? As long as you're using the Fiber>Analog adapter, you can use any of these Android HUs?

Also, is Nav directional information also passed to the instrument cluster as it is with COMAND?

Also, as a 211 bluetec owner, congrats on 410K miles!!! holy shit!

Can you provide a list of all the parts required to complete this install?
 
#11 ·
As long as you're using that fiberoptic adapter, you could potentially install any head unit you wanted. you could install a $1000 top of the line double din touch screen head unit if you wanted, or just a simple cheap $50 one. (not sure why you would do that over staying OEM command..?)

Nav information is not displayed on the IC. i didnt even know that was a thing, my car never originally had NAVi. ive got google maps set up with my head unit now, and it verbally tells me the directions turn by turn, as well as put an overlay over whatever app you're in telling you when and where to turn. its great. (i usually just go wherever the google lady tells me:grin)

all the parts needed for this are in the original post. but just to reiterate:
-fiber optic adapter
-head unit of your choice
-solder/shrink tubing, scotch locks, crimp connectors (whatever method you want)
-a couple dozen feet of 16-18 gauge wire for can bus connections and splicing. (i used high quality speaker wire, that way you can run +&- in the same line)
-6m antenna patch cable.

Other than the fiber optic interface, this really isn't any different of a procedure than installing an aftermarket radio in any other car.


And thanks!! i actually bought the car from the original owner at 398K!!:eek
i got a hell of a deal on it cause it was such high mileage. The build quality of these W211's is absolutely incredible. at 410K miles, original engine, original tranny, absolutely NO rust (even on the under body, its incredible. AND its been a Michigan car its entire life.) ive owned a 83 300SD, 86 190D, 91 300D, 95&97 C280(god i hate C Class's), 99 E300D, and now this 2005 E320 CDI. after owning and doing all my own maintenance on all those cars, i can say the CDI is my all time favorite. Best Diesel sedan MB ever made in my opinion. :bowdown:
 
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#12 ·
Thanks for the follow-up and good work. Apologies, but a couple more questions:

1) You mentioned you're using google-maps on the HU you chose. Does it require a tethered network connection to work, or does it download and keep a local copy of google maps?

2) Any tips on the best way to route wires to the rear?
 
#15 ·
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#14 ·
Google maps normally does require an internet connection, but you can download offline maps for you area (i did the entire state of Michigan). Without an internet connection, you can search for address's as well as business names and such and it will give you complete turn by turn directions.
I use the mobile hot-spot app on my phone so the head unit can connect from time to time, so i can download and update apps. It does NOT need to be connected to the internet all the time for it to function properly though.

Frank, that communication is all determined by the can bus communication. The can bus box for the radio is probably not converting the GPS directions into the CAN-B network. I DO think its possible, i just don't think that's been done yet.
 
#17 ·
Since you connected to the front RCA outputs instead of the rears does that mean you still have control of fade from side to side and front to back?

i have fade control from side to side, but not front to rear. the f-r fader just basically just fades the output completely.
 
#18 ·
Does this most adapter work on the cls? I talked to avin and they say no even though I think these cars use the same audio setup. I talked to ali express who sells a most unit and they say yes and it's labeled as working for eclass cls, s class cl class etc. So I dunno.
 
#19 ·
Hey Dnasty! just reiterating what i said on MBworld. :wink

From my knowledge, the CLS uses the identical audio system as the E class. so if i were to take a wild guess, i would say that the Avin E-Class module WOULD work for the CLS. The MOST communication system used in these cars is not specific to just Mercedes, there's a few other car manufacturers that use it as well. so i would imagine the actual digital communication "code" is not going to differ between Benz vehicles. If you look on Avin's website, they list 2 most interfaces for Benz. One for the E class, and one for the ML/GL/R. From what i can tell, the only difference is that there is a "wake up" wire on the ML/GL version that gets 12V when the key is on. So i guess that it would work. if you're feeling adventurous, you could contact Avin to see if they offer a money back guarantee/ returns? Maybe you could try it out for the CLS and see if it works! Avin's got great customer service, so its worth a shot.
 
#20 ·
2009 E63 stereo

I just ordered the exact parts you listed for my E63, will report back how it goes, I don't quite understand the part about grounding the wires because of interference from the engine, can you explain that more, I heard you talk about it in the video but no mention in your write up or I missed it.

Anywhere special to get the antenna cable? I'm just going to have a local installer put it in, will probably print out your instructions as well. Thank you very much for providing these details, my Comand unit just crapped out the other day and this looks like an awesome upgrade.
 
#22 ·
I just ordered the exact parts you listed for my E63, will report back how it goes, I don't quite understand the part about grounding the wires because of interference from the engine, can you explain that more, I heard you talk about it in the video but no mention in your write up or I missed it.

Anywhere special to get the antenna cable? I'm just going to have a local installer put it in, will probably print out your instructions as well. Thank you very much for providing these details, my Comand unit just crapped out the other day and this looks like an awesome upgrade.
sorry for the confusion! when i wrote that tutorial is was still messing around with wire routing and cleaning up the install a bit.

i actually removed the ground loop isolator i installed (so ignore that step) and instead installed one of these () + noise filters. You use that to power Both the HU and Avin box. it filters out any noise that may exist before that point. That completely eliminated the engine noise for me. install instructions for that are on the box it comes in.
(i did away with the ground loop isolator because it actually reduced my sound quality quite a bit.)


As for if all this is available in Australia, i have no idea. you'd have to contact AVIN.
 
#24 ·
You could just use a loc and tap into the woofer in the back but the fact that you are mentioning getting the avin most leads me to believe you are getting an after market headunit which usually comes with independent subwoofer rca outs which would be even better to use.


Sent from my iPad using Tapatalk
 
#25 ·
I am considering an aftermarket headunit. I'm looking at the droid units that have an OEM look and I'm trying to decide whether to use external amps for both full range and subwoofer; or, keep the factory amps on the full range and a separate amp for the subs. I'm just not sold on the quality of the droid units although I'm hearing good things from those on the benz forums. The major issue I'm sorting through is how to get good base. I have a CL600 with the factory free air/infinite baffle sub and I'm thinking of using a new/old stock JL Audio 10IB4 which is one of the best free air subs of all time (I actually have a pair). The trunk of the W215 is small so I'm not keen on a box. Plus there's no way to get air through the back seat. I'd love to hear any positive feedback from anyone that's do free air with success in the W215.
 
#26 · (Edited)
That's funny I'm also on the merc forum and looking to do similar upgrade to my w219 cls500 with one of these headunits but there's literally no info on the big screen ones everyone seems to get the rk3188 7 inches unit. I'm sure you're following the android headunit post on the guys eclass as well. I put two subs in the trunk of mine so the bass is a non issue but I assume your car has a much smaller trunk. If you don't want to do any major work I'd go for a low profile single sub and get the box with a port going up. I should also probably do that in my car. If you're adding a new amp in the car you might as well remove the stock sub and put a better sub there and run the sub out from the amp.
 
#27 ·
I'm really interested in knowing if full screen mirroring works with iphone! About to pull the trigger on this one :)

Is it possible to change the color of the backlight to match that of the car? This backlight is more red which doesn't look like it is matching...?
 
#28 ·
answering private message with a full PM box

answering a PM, hit the reply button, found out the guy had a full PM box. SOOOO im posting it here, hopefully helping anyone else needing clarification.

"I have been using your post as a guide to install an aftermarket stereo in my w211. So far, I have managed to get every thing working except for steering wheel control. After rereading your post, I realized that there are a couple things that I cannot figure out. Using your post, I have purchased the head unit, and AVIN MOST box as you have recommended. But I cannot determine which wires coming out of the CANBUS are the CAN wires that I need to connect to the brown and brown-red wires in the CAN bridge. On the head unit, two wires, white and blue, are labeled as CAN-TX and CAN-RX. These two wires come out of the head unit harness and plug into the CANBUS box. But there are no CAN wires coming out of the CANBUS box. (in a youtube video, CANBUS box is shown to have a pair of blue and white coming out).
Also, you had listed that you needed "a couple dozen feet of 16-18 gauge wire for can bus connections and splicing" . How many splices did you have to make from CANBUS to CANBridge?
I feel like I have been running a marathon with this project, and now facing a huge hurdle just before the finish line. I really hope you can get me across the finish line. Thank you for your time."




If i recall, the CAN-B wires that need to be connected to are the 2 green wires (Green, Green/White?) in the main radio wiring harness. i believe the wiring "glossary" is printed on a sticker on top of the Head unit. You just need to connect those green wires to the brown, brown/red wires. I cant remember the correct color combination for which colors connect together in what order, but if you get the CAN connections wrong its not going to hurt anything, just flip-flop them out and the CAN controls should work!

Good luck on this project! it was a fun weekend project for me getting everything working, but the end result was way worthit!
 
#29 ·
These are all the wires and harnesses that came with the head unit. None of the harnesses have the green green-white wires that you describe. I do see the wires that you refer to in a YouTube video. But they are not present in any of the harnesses that I received.
 

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#30 · (Edited)
what are those 2 green wires coming out of the white CAN BUS box connector? I see them in both the pictures. you also have green wires coming out of the black HU connector. What are those? i remember the can wires from the CAN box being green. the sticker on top of the HU, what color does it say your CAN connections are?

Remember, the incoming CAN communication from the car goes into the CAN BUS BOX input, NOT the radio input.
 
#32 ·
If you're still having issues. You might want to contact the manufacturer and ask them for help.

And yeah. Try those grey wires first that are labeled "can." They may have changed the wiring colors since I did my install a couple months ago.
 
#33 ·
Following your tips, I rewired the connections again. The green and green-black wires coming out of CANBUS box are indeed CAN wires. I also discovered that the CAN-bridge wires are in one of the plugs that connect to the original CD player. I did not have to dig through the door sill at all. Now I have SW controls. I did this rewiring last night using just a flash light, and was extremely happy that I have SW control. This morning, I notice the following:
1. The stereo powers on right away as the key is turned to first position.
2. The up and down buttons on SW tune the radio. They do not go from one preset to another.
3. As I shift gear from Park to Drive, or from Drive to Park, stereo would cut out and back up camera screen comes out briefly.
4. When I turn off engine, I hear a audible pop coming from the speakers.

These are the connections I made last night:
1. Yellow wire from MOST box + red ACC from HU to constant wire, striped brown wire, in cigarette lighter.
2. yellow wire from CANBUS to power wire on plug (it had the fiber optics that went into the OM sstereo)
3. Both black ground wires from MOST and CANBUS boxes are connected to brown ground wire on cigarette lighter.

What concerns me is the pop that I hear when I turn off the engine. Should I modify the wiring?
 
#34 ·
had the same problem when i first wired it up. Easy fix. You wired the fiber interface to a Switched circuit. It NEEDS to be wire to a constant on circuit. the fiber communication system has to be able to communicate even when the key is out/off.
 
#307 ·
I Rossafuss. After some tests i found out that my fiber interface box was drawing 70mA extra from battery so i connected it to Acc instead of constant and know i too have the pop-up sound when i switch off the car. Is there anyway to prevent that battery draining from the fiber box when connected to constant 12v?
 
#36 ·
Canbus wires?

Hi,
I have been following your plans for the install of a new HU. My MB is almost identical to yours I think -- 2005 E320 CDI. My question is this: There were 2 connectors on the back of the original HU. One had the two fiberoptic cables plus 3 wires that I determined were +12v constant, +12v switched, and ground. The other connector had 3 wires -- one was brown and the other 2 were messed up due to the tape that MB used. One could be brown with a black stripe and the other yellow though really hard to say for sure with either one because almost all of the color rubbed off (?) with the tape. Do you think that this second plug could be the Canbus? I am installing the Avin Avant2 with MOST adapter. Also, where did you tap in for power to everything?
Great thread BTW. Really helpful.
Thanks,
CP
 
#37 ·
Hi,
I have been following your plans for the install of a new HU. My MB is almost identical to yours I think -- 2005 E320 CDI. My question is this: There were 2 connectors on the back of the original HU. One had the two fiberoptic cables plus 3 wires that I determined were +12v constant, +12v switched, and ground. The other connector had 3 wires -- one was brown and the other 2 were messed up due to the tape that MB used. One could be brown with a black stripe and the other yellow though really hard to say for sure with either one because almost all of the color rubbed off (?) with the tape. Do you think that this second plug could be the Canbus? I am installing the Avin Avant2 with MOST adapter. Also, where did you tap in for power to everything?
Great thread BTW. Really helpful.
Thanks,
CP
Sounds like your second connector would be the AUX/iPod interface (WH, BN, TR). The first one has power and ground but the third wire is not switched power but the MOST wake-up signal.
 
#38 ·
Canbus?

OK. Thank you. I do not have an AUX/Ipod interface present in the vehicle though I understand that they may have put these connectors in for the future. Is there any way to test various wires to see if they are the Canbus wires? Perhaps using a VOM meter. I do not know, just a thought.
 
#39 ·
OK. Thank you. I do not have an AUX/Ipod interface present in the vehicle though I understand that they may have put these connectors in for the future. Is there any way to test various wires to see if they are the Canbus wires? Perhaps using a VOM meter. I do not know, just a thought.
You could try to measure the "no activity" voltage from CAN wires but there are easier ways. First of all, CAN wires are a twisted pair, a quick visual inspection should be enough.

You did not mention which head unit you have but I understand you did not have speaker wires at the head unit. That means your W211 has an AGW at the trunk and CAN wires go to the AGW, not the head unit.

You can check all this from the wiring diagrams (WIS or MB model specific workshop media).
 
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