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I just replaced my OEM Harman/Becker BE 7024 Comand unit with an aftermarket radio in my 2005 E320. I retained the factory amp and speakers, so I used a fiber optic interface. I also installed a steering wheel controls interface to retain the use of the steering wheel buttons. I documented the entire process in a lot of written detail, but not with pictures; hopefully, the descriptions are clear enough to follow. The document is 6 pages long, so I am posting it as a PDF versus taking up a lot of space in this post. I took a couple of pictures of the finished installation.
I mounted the USB and AV OUT connections in the cigarette lighter compartment so they can be concealed when not in use.
Last edited by oldsports; Apr 13, 2020 at 10:17 AM.
Reason: Corrected items in PDF attachment
Nice write up, and model specific to my own! I've been considering adding modern features to my 15 year old car and you've done the legwork for me. Thanks for that! I've got a Pioneer AVH2550 that I installed in my '05 Chevy pickup and I love it. Android Auto is pretty darn convenient, and having a back-up camera mounted high on the bed topper is really nice for knowing where the back of the truck is.
Do I understand correctly that you also installed a back-up camera? Where did you mount the camera on the rear of the car?
@rapidoxidation I have not installed the camera yet; I will probably get to that this weekend. The camera I purchased mounts in place of one of the license plate lights. I purchased it on eBay from China; the link is below. It was fairly cheap so I am not expecting really high quality; I wanted to try it out since the radio supported the rear camera feature. It should be easy enough to swap out later for a higher quality camera if I want to since the tough work (running the camera feed and reverse signal wire) has already been done.
@Azeem Thanks for the suggestion. I saw another post were someone had placed a microphone in the center dash grill. I have a speaker in that grill so I was concerned that I would get feedback from the speaker when I used the microphone. I wrote to the person to ask for his/her experience with having the microphone there (assuming they had a speaker there) to see if my concerns were valid but they did not respond. Have you put a microphone there before? Does the speaker cause feedback when you use the mic?
Apologies, I haven't installed the microphone but the person on a forum did it successfully without interference. You might want to try, if there's interference you can revert it back to another location.
@rapidoxidation Since you asked about the back-up camera, I figured I'd let you know how it went. In general, it was not too bad but I did make one error that hopefully you can avoid if you attempt it.
In my initial write-up I discussed how to run the video and Reverse feed from the back of the car up to the head unit in the front of the car so I won't repeat that here. I am starting from the point of having those wires in the trunk. I used this YouTube video to guide me through the process:
The video was very good, but it did not have any verbal instruction. I followed it fairly closely, but here are some additional things I did and the error I made:
I tapped into the tail light wires as in the video (Yellow/Grey - Reverse, Brown - Ground), but I did not do it right at the connector as they did. Instead, I made my connections further down the harness about 2 feet away. I figured that if someone has to perform maintenance on that light assembly, I did not want them to have to deal with the wire taps coming right out of the connector.
I used a 12V rectifier on the wire taps I made into the reverse tail light wires. I want to ensure that I am getting a constant 12V feed for the camera and the Reverse signal that goes to the head unit. I don't know what voltage level the reverse light is, but the rectifier ensures that it will be 12V on its output. I installed a back-up camera on another car without the rectifier and the picture jumps a lot. I believe it is because the assembly is not getting a constant 12V. I plan to install a rectifier in that car to correct the problem.
I found out that a hole needs to be made in the plastic assembly of the license plate bulb housing in order to feed the camera wires into the trunk. I used a drill to make a hole, but when I did that I broke a retaining clip that was holding the housing in place and it became loose. I noticed that on the video, the installers used a heated soldering iron to burn a hole in the plastic; this was probably to avoid the mistake I made in breaking the mount with the drill. Since there was no verbal instruction in the video, there was no opportunity to get that advice before I made my error. I used some clear silicone sealant around the outside to stabilize the housing, but it will make it a pain to change the bulb because I will have to strip off the sealant in order to get to it.
I did not have to modify the plastic lens on my camera unit like they did in the video. My camera fit perfectly in the opening and I was able to mount the bulb just like the original lens cover. The bulb still works!
Other than breaking the retaining clip on the license plate bulb housing, I am pleased with the installation. The camera's picture is actually pretty clear. I only tested it during the day; I don't know how it looks at night. I am including pictures of the tail light harness (so you can see where the Reverse wire is) and the rectifier that I used (purchased for $6 on Amazon).
Last edited by oldsports; Apr 16, 2020 at 05:32 PM.
Reason: Added additional information
I dremeled a hole in the flat part under the cigarette lighter. I was a little heavy handed with the dremel and ended up having to add a little super glue. I also had to cut and shorten the cables because there was too much slack and was too much to tuck in behind everything.
I also ran two long USB cables (head unit has 3 USB inputs) through the center tunnel, beside the shift assembly, and into the center console compartment
Here's the finished product. Sorry for the dirt. I haven't had a chance to clean my car in a while. I still have the old dual USB charge adapter in the cigarette lighter because I don't have the cover for it and I didn't want to have the hole staring back at me.
@rbc3az I like where you put your AUX/USB connection - I did not think of that. It would have also saved me some storage space, especially since I lost the storage space I was hoping to gain in the CD changer slot now that the door won't open!
Nice write up and it looks good. Can I suggest that you reconsider placing your microphone inside the center dash grill.
@Azeem I received a response from the person I contacted about the microphone he put in his center dash grill. He did not use the fiber optic system like I did; he re-wired his system to use his aftermarket system's amplifier. The amplifier did not support a center channel (just left, right and sub-woofer) so he removed his center channel speaker; this allowed him to place a microphone in the grill without interference. Since my center channel speaker is still in use, putting a microphone there will not work for me.
How is your sound quality? Do you have fader or balance? How powerful is the stock subwoofer in comparison to before (can you crank it up to be louder than it was stock?)
@tartilc I don't detect a noticeable difference in sound quality versus using the OEM head unit. As I mentioned in my write-up, I am not an audiophile so my requirements for sound quality are not as high as others. I have balance (left and right) but not fade. The fiber optic unit only uses the LF and RF outputs from the aftermarket head unit and uses them to feed all channels. Since there is no Rear feed, this means that there is no fade control. I have not tried cranking up the sub-woofer so I don't know how loud it gets; I'll have to try it and report back. I get the amount of bass I desire so I have not had a need to crank it up. My guess is that it won't be as good as stock since it is feeding the sub-woofer with LF/RF versus a feed specifically designed for the sub-woofer (as I assume the OEM head unit did).
I see, yeah that's my only real gripe, while I'm also not necessarily an audiophile I can't rationalize the upgrade if it means a decrease in the sound quality :/ Always wanted a bit more bass out of the system. I've been looking into that La Power unit along with some method to add a reverse camera to the stock display so I can fix my main issues with the system while keeping OEM looks. Would still lack carplay/android auto and whatnot though which sucks.
@tartilc I have seen posts on installing a reverse camera on the stock units. From what I understand, the stock unit needs to have a video connection (green Fakra connector) already installed and you have to do some programming of the COMAND unit to turn on the connection. My COMAND unit is an NTG1; it does not have a video connection so that was not an option for me. You'll want to make sure your unit has a video connection before you proceed.
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