Axe Murder

Hello! Are there any people out there who have already upgraded their head units who can help me make sense of this?

Have: 2009 E500 with COMAND NTG 2.5 and Harman Kardon.
Bought: Erisin ES8580E and the auxiliary BZ6M cables supposedly needed for HK systems.
Did not get: any type of instructions or even a paper explaining what components I am looking at.

I sent them a "Really?" mail, awaiting some sort of reply which will probably read "We can't keep notes on how to do it for all of the 200 car models we support!".
We shall see. They have precious little information at all on their site.

Can you help me sort this out?



I am assuming these things based on how they are labeled. Not sure about the GPS antenna though.

Not interested in any of these except the GPS antenna. I guess the "SIM/speakers/dashcam" stuff is for like extra speakers or monitors in the rear seat?

And I sort of assume that I do not need the mic? The car has Bluetooth handsfree today - where is the mic for that?

Rear of unit:

Nothing really weird here, except the optic connector (black, lower left) which I have no idea what it is for.

The old NTG 2.5 (below) has antennas for AM/FM radio (double white), GPS (blue), Bluetooth (yellow). The green connector is for the (non-present) reverse camera.
The large square connector is supposedly for speakers, fiber and power. One can see the light from one optic fiber (pink cuffs) to the upper left.


Now the confusion commences.

An adapter was bundled with the Erisin:

It has no fiber optics and only connect to the smaller rectangular set of pins on the female end.
The yellow label warns me to ensure that ground and power are right, or the fuse will blow.

And then we have the 6 meter long auxiliary cable harness:

They have one large square in one end, three other connectors in the other end, plus one separate thing that looks like a coaxial.
I am guessing one of those three connectors is for the CAN bus - is that what receives the signals from the steering wheel controls and such?

Now please tell me if I have figured this out right:

1 - The long auxiliary cable should be connected to... something... at the rear of the car, using the three connectors. Also the coax beside it.

2 - At the head unit, I should simply not use the existing large square connector but instead the one on the new auxiliary cable.
This is the only way I can make sense of it. The car one is a male, the Erisin has a female, the long harness is male, the adapter is a female-to-male.

3 - I should not use the adapter thingy, it is meant for cars without the Harman Kardon.

4 - I do not need to use the silly little antennas bundled, I can use the ones already in the car.

5 - I am supposed to disconnect the fiber optics and not use them.
But does this mean I should somehow loopback them, like people seem to do in some videos? I got nothing for that in the bundle.

I have no idea what the coax is meant for. Some video indicated that it was "radio antenna" - but why then is it not double? Like the already existing one?

Do I need the mic for handsfree phone? Does the old NTG 2.5 utilize some sort of mic that will disappear with the unit?

What is the fiber optics for, really? Since we supposedly do not need it...

I am quite confused by how the connections differ in the large square connectors - I mean, the one in the car has leads to the rectangular sets, the Erisin has pins there, but the adapters and long harness are empty there.

I am grateful for any shared wisdom in this subject.

Axe Murder

Crikey! Right after posting this I clicked on the links to see if they worked, and randomly found a certain amount of information I had missed before!

Under "Photo Gallery" for the auxiliary harness there were some instructions.

Yes, I am supposed to plug the large square into the Erisin, bypassing the one already present.

The three at the rear are for power, speaker and CAN bus.

The coax-looking thing ("Fakra radio exension") is indeed an antenna whose single connector goes on one of the double ones on the head unit. I am guessing one is for AM and the other for FM? I never used AM once in my life so if this is for FM only then that is fine.

Same thing with the head unit itself - under "Photo gallery" below a long list of feature bragging there is actually a bit of information. Listing what the bundled stuff actually is.

I must be very old to expect such things to be supplied with the components. A printed paper. Not at the bottom of a photo gallery.

Axe Murder

I feel I ought to keep documenting my trials and tribulations for posterity.

The Erisin site showed (among other things) this info:






Remains to find out where to connect those in the trunk.


This is what it looks like in the trunk:



The white thing to the left is presumably the AIRMATIC pump.
The flanged thing is the car computer, I guess?
To the right is a rack with fuses.

Behind the Flanged Thing is this:


Two boxes whose article numbers return "Control Module" (211 545 00 16) and the other one (211 545 51 23) does not return anything on Google, but a seemingly identical one (211 545 51 32) says "Towbar Control Unit". Alright.

It has an awful lot of connectors for being a towbar control unit, tho...




Then above these boxes I find this, whatever it is.


Now - what do I connect where?

The fiber optic/CAN bus thing looks easy enough, it is on top of the Flanged Thing.


And this is the #4 connector that goes there.

But these two?

Axe Murder

My browser b0rked. I guess there were too much JavaScript or something going on what with all the pictures. Luckily I could submit what I wrote so far.

Anyway - I need to figure out where those two last connectors are supposed to go, and the separate antenna cable.

Also, I am puzzled by the fact that there are no instructions on making a loopback connection for the fiber optics. Is that not standard procedure?

And: IF that is the CAN bus connector and the Flanged Thing IS the computer - should it not go to some splitter thingy? I mean, it would be daft if I unplug the one and only connection to the computer to wire in the head unit, thereby cutting off all the other devices that rely on it...?

I guess it may also be the case that the Flanged Thing is actually not the car computer at all, but a stereo amplifier or something?

If any of you have any insight, I am all ears. Thank you in advance.

Axe Murder

I'm an idiot who fail at reading upside-down pictures. The unknown black box has article number 211 545 51 32, not 23,

It is an Anhängeranschlußgerät. Or "Comfort/convenience module", or "Tailgate Trunk control module" or "Towbar control unit" depending on where you look.
Whatever it is, it is not related to the head unit.

And the Flanged Thing is not the car computer, because that looks different.

I did find pictures of the regular Harman Kardon amplifier which seems to have the connectors I am looking for - but it does not look like the Flanged Thing at all.

However, after a LOT of searching I found that it is a "Harman Becker" amplifier, A2118703794 or some such. Seems to be a late model most commonly found in the W204/W212.

Thing is, it has different connectors. No wonder I could not find the proper ones.

Axe Murder

Again, for posterity and clarity, this is the amplifier:


This is its connector:


This is the older amplifier's connectors that the wiring harness expected:




I still do not know where I am supposed to connect the long antenna cable.

Axe Murder

Update: I got nice support from Erisin!

First some information that I had already sleuthed myself above, then when it turned out that my amplifier was a late-model thing different from what was expected, they offered to replace the long-cable harness with an optic decoder unit instead.

Relieved that I will not have to pull cable beneath panels in the car. I will have to splice some small cables for power, etc, but it may be simpler overall.

Axe Murder

The fiber optic module arrived.


I get that I should transplant the fiber optic connector and where to plug the red and white audio connectors.
I also think I know where to splice the yellow power and black ground.

I am not so sure about the red ACC cable though.

Axe Murder

On the head unit there is a pinout diagram showing ACC.



Which is supposedly this cable.



But is that ACC out or ACC in?

I am guessing out, since that bundle of cables is meant for reverse cameras, but I am not sure.

Electricity is scary even without the label that warns me that I will blow a fuse if I get it wrong.

Axe Murder

NOPE, I AM GIVING UP AND SENDING EVERYTHING BACK.

The lack of information makes this ordeal impossible.

I have a late model W211, it was built in September 2008.
The connectors on the rear of the NTG 2.5 look nothing like any pictures or instructions I obtained or find.
The amplifier is not the same as in the pictures or information I find.

It seems - though I cannot get any confirmation - that the blue box is meant for W212 systems.
It seems - though I cannot be sure - that my W211 does indeed share that with the W212. Probably because it is a last-year model and they transitioned to new components by then.
It seems thus that I might be able to use these components, but it is all stabbing in the dark and I would prefer not to do all the work only to realize that I was wrong.

I cannot find out how to connect to the CAN bus, because nothing in any description matches.
I cannot find any ACC cable, and prefer not to experiment by pulling cables all over the car only to be stumped by false assumptions.

So I am throwing in the towel.

Axe Murder

VICTORY!

Since I am a reckless fool, I decided to give it a final attempt - and got it working perfectly! I think.

All the information I managed to locate on the web seemed to indicate that the gear in my car is a generation newer than in most W211. The amplifier is not the same as in all the photos I found, the connector on the back of the NTG 2.5 was a large square thing whereas most photos show a smaller connector with fewer wires.

The Erisin head unit has a large square counterpart that looks a lot more like that in my car.

The short adapter they supplied omits a bunch of cables in a fashion that looks downright medevial, so my head went "What if this 2024 head unit was manufactured with newer systems in mind, and that adapter is meant for the old stuff?"

So I plugged the car connector directly into the Erisin and turned everything on. It booted nicely, seemed to run as it should, but there was no sound. Probably because I had not hooked up anything else.

So I took the blue fiber optic box and moved the fiber optic cables to it, and hooked its ACC, GND and 12V cables to counterparts that had the same color and labels on one of the bundles that plug into the Erisin. I had no idea if it would work, but a hunch, and it did.

Still no sound from the FM radio even though I did plug in the car antenna (a double white thing). So I put a micro-SD card with MP3 music on it into the Erisin socket (behind the lower left buttons) and lo and behold: perfect sound! From all the speakers, as far as I can tell.

Then I paried my phone over Bluetooth, and it seems to do Android Auto and stuff just as it should.

Even the steering wheel controls work, and the gauge cluster shows proper information about what the head unit is doing.

Remains to plug in the GPS and other antennae on the rear and see if I can get FM radio going, but even if any of those would struggle then Android Auto covers the bases.
Also, I have to check if the handsfree speakers/mic work as they should when making calls.

I am happy!