Mehrish

Hey guys,

I am from Sydney, Australia and am new to this forum, although i have visited several other threads on this website over the years as i own several mercedes cars and have always found them to be helpful. Hope I find something through this thread too.

Today, I am looking to solve an audio issue I have.

Here's the problem - I just bought this car 2nd hand after its been driven 250,000+ km. No problems mechanically just one issue. Now the issue is that here is absolutely no sound. No sound at all, not from the radio, nor any CD's, the media interface, bluetooth audio, even no audio from bluetooth telephone. Just nothing. Everything else does work though. Navigation works, i can move around the menus, change settings everything. Just no sound. Now this issue has been apart of the car since i purchased it, so i have no idea what may have initially caused the problem. I have tried to ask the previous owner questions in regards to this, but he seemed to be rather unhelpful. Maybe because he was happy to get rid of the car, even at the low price he was asking for it. Probably knowing what the isssue was.

Anywho, here's what I have done to try and rectify the issue -

As a first step, i took the car to an audio electrician to try and narrow down the possible faults. Now from that inspection i found out that all wires, including the fibre optic connection were working perfectly fine, as were each and every one of the speakers from all around the car. Therefore, from what i gather, the inspection electrician and every one else ive spoken to since, say that the amplifier is the first culprit. So naturally i worked on finding one to replace.

Second, after finding a working amplifier from a reputable euro cars wrecker, i happened to install the new amplifier. Much to my dismay, this did not solve the issue. Heartbroken and still unable to listen to the beautiful harmon kardon system, i decided to get a second opinion.

Then, by getting a second opinion and informing the second auto electrician of the alternate ampifier i had purchased, i was told that both the original and replacement amplifier seemed to be working fine and that the next and most probable culprit is the head unit. NOW THIS is where my headache truly began.

After finding out the head unit might be at fault, i was told sourcing an alternate head unit from a wreckers should be my next move and should most likely solve the problem. Although, i was warned that mercedes may have an anti-theft system in place that prevents installing parts from one vehicle to another and that installing a new head unit might only be successful with a radio code and some programming; both that would most likely be provided from the services of Mercedes. Is this true? Will the car require a codes and programming or should just be as simple as plug and play?

After being told this, I have done a ton of research online in regards to whether a code and programming is truly required, how easy getting these steps completed would be, how much it would cost and what my alternate options could be. To be honest I found several answers, most that seemed to be contradicting each other. So any opinions and answers you guys have on this would be of great help.

Now, with all this information. I made my way to my local Mercedes Benz Dealership, where i was informed that installing an aftermarket unit should be an easier and more cost efficient solve than purchasing a unit from a wrecker and getting it reprogrammed for my vehicle.

While the aftermarket unit may solve the problem, im afraid i might lose some of the features of the car and may not even receive the same exceptional sound quality i would otherwise.

Anywhos, keeping my options open, i then went to a nearby audio shop to find out if an aftermarket unit can be installed and how much it would set me back. Now at first i was told my issue should be able to get resolved but i would first have to purchase a kit that would shuffle around certain parts of my dashboard to allow an aftermarket unit to be fit. A kit that would set me back $1300 before even purchasing a head unit that would set me back another $600-$800. And these are just the costs for the parts, not even labour.

This pretty much rules the option of an aftermarket unit out, considering i still am at the risk of losing certain functionality. Unless that is my only option to get the damn thing working.

With all this information and with my mindset of trying to solve these issues on my own, i did tons of more research and even spoke to some mercedes repair specialists around Sydney to try and find out if i have any other options at all. From all this grovelling, i gathered that at times, the software can have programming and compatibility issues where the head unit doesnt interact with the amplifier properly and therefore provides no sound. Apparently the work around to solving the issue if this were the case would be to set the system in a way where it believes there is no amplifier in the car and the unit needs to run without it. Then, immediately after doing so, re programming the amp to the head unit from scratch through the use of an audio specific diagnostic tool that only mercedes has access to. TO ME, this seemed to be somewhat of a hunch and that my issue can only be perectly diagnosed at a mercedes benz service center. Is this at all the possible cause? Do i have to maybe not purchase a head unit after all?

SOOO, this brings me back to stage 1, where i am no longer really sure what the issue is and no longer sure what my next move truly is considering Mercedes themselves recommended i opt for an aftermarket unit. I am since wondering maybe Mercedes is not interested in sitting for hours to reprogram another head unit to the car and putting the effort in for a job that is not worth its money.

Anyways, I am honestly looking to keep an original Mercedes unit but have no idea what route to take to get the issue solved.

In summary,

I am wondering if a replacement head unit from a donor vehicle will solve my issue plug and play or is the anti theft code as well as vehicle specific programming required?
Also, can it be a simple miscommunication issue between the amplifier and the head unit that is causing issues with sound? Will a little programming at the dealer with the cars original parts do the trick?
Would an aftermarket head unit be the only option i have?

Anyone who has experienced this issue in the past, please do let me know. It would be of so much help you cant even imagine it.

Well, thanks for reading everything if you did. Sorry for making the message so long Hope to hear from someone soon

Take Care Always
Mehrish