Rudeney

Pull the fiber optic cable from the amp (in the trunk, behind the carpet, right fender) and check for light. You'll see it if it's working. If not, then the fiber cable is broken or unplugged somewhere along it's continuous "ring".

SAFETY EDIT: Don't look directly at the end of the fiber cable - point it at a white piece of paper or just look at it from the side in the dark.

JDCLK5

Okay so im going to check it this afternoon. So the light should be comming from the fiber optic cable itself? And i know there was forsure a red light on inside the amp when i looked last night does that have a meaning? And the amp im guessing is the larger of the two rectangular boxes in the rear passenger side trunk space.

JDCLK5

the red light is on constanly with stereo on. then i just had an idea to unplugged cd changer fuse then the red light blinked and kept blinking till i put it back in then still constantly red, i'm thinking a broken spot in the loop or bad changer. any ideas??

Rudeney

Unplug the fiber optic cable (the stiff orange wiring, always in a pair). On the end of the connector, there will be two lenses - one white one red. You should be able to see light in one of them. If not, then there is a break somewhere in the fiber ring.

JDCLK5

Okay i took it to a family members garage, has the best scanner around. U1000 code came up with a short in the circuit. But wasnt able to tell me anymore. Any ideas what part could be throwing off the system.?

Rudeney

I'm not sure what "U1000" is. I can't find that in any of my documentation. The native codes for the sound system look more like this:

http://benzbits.com/SOUNDcodes.pdf

I am not aware of any non-MBZ scanners that will read these codes.

E46zhp

i unplugged the fiber optic cables from the amplifier and turn on my radio and i had the Amp blinking once but nothing from the fiber optic cables....? then i did the same with CD changer, the CD changer and fiber optic cables both blink twice!.. then i put a flash light on the fiber optic cable end and i could see the light coming thru the fiber optic cable at the AMP and the CDC...

i have the same problem as stated before
"its weird the radio is on, no sound is coming out, when i hit cd, it says no cd changer when there is one in the glove compartment"

mjaccim

I had same issue pulled the "sound system" fuse #26 and replaced and sound came back on...

Hope this helps...

MJACCIM

TheNoble

When you try to eject the cartridge does it come out or does the eject button just blink green?

DanielFD

ok I have of experience with this, hopefully it can be of some help. The D2B system works in a curious way. there's the fiber optic ring and then there's the D2B wakeup signal that runs through the cars wiring. basically the D2B wakeup signal sends a signal for the component that needs to be turned on, be it that amp or CD changer, then that component turns on to accept the light passing through the fiber optic cable that in turn passes on the signal and so "the D2B ring". When I retrofitted command 2.0 I faced an annoying problem. I plugged in everything but go no sound from the speakers. I tried restarting the optical ring through star and still got nothing as if the amp and cd changer wasn't installed. at first I thought my connections weren't tight or my D2B wakeup signal wire wasn't passing enough current. I eventually unplugged all the fiber optic cables and tried cleaning them, nothing would work. Even on STAR I couldn't get the command to see my amp and CD changer. Eventually I noticed that I was getting that one blink from the fiber optic wire then it wouldn't turn on anymore. On my last try I unknowingly plugged in the D2B connector into the headunit before plugging in the power connector (B connector, if i'm not mistaken). somehow everything worked.. I then opened STAR and configured everything. I'm guessing when the power is first given to the headunit it will conduct a small search through the ring to tell if it has anything plugged in, if it finds nothing then it shuts it down. I think while having everything plugged in pulling the fuse and putting it in will probably solve your problem. If that doesn't work then you need STAR to reconfigure the D2B network. (D2B is very unstable, that's why it was changed to MOST, it is possible your headunit forgot its configuration)

DanielFD

Also as a side note, i also had a similar problem in my c class. Whenever i went into a pothole i would loose sound. And then id find another pothole to hit to get the sound back. Try explaining that to an audio specialist.. Eventually i found out where the amp was and pulled it out and it was fully packed with dust. It seems insulation backing peeled back on the inside of the sheet metal and desingrated into dust and filled up the d2b connector on the amp; hence the potholes' effect on my audio system.

DRACO

Bringing back an oldie but goodie :-)

So wife's Cabrio sound no more but radio turns on and aux for ipod was displaying on the gauge but no giggity giggity.

Removed and Replaced fuse 26, No Joy ( Left Side Dash )
Removed and Replaced fuse 64, No Joy ( Engine Compartment Driver Side )
Removed and Replaced fuse 20, No Joy ( Trunk Driver Side )

Thought about it for awhile then deduced the 11+ year old fuses may have too much resistance? In any case, I decided to put emory clothe to all of them.

Removed them all at the same time and polished with emory clothe, to insure Radio is in fact dead, I turned the car to acc. Gauge Display shows: "Radio ---" = DEAD.

Placed 64 first, 26 second then 20 last.

Wait for it..........................

Turned key to acc, We have SOUND :-) giggity giggity :-)

I wonder how long it will last but, if I have to do this twice a year, I can live with that or save up to change the entire system out for a bluetooth ready with navi unit. Who listens to CDs anymore, right?

Jim

DRACO

So far so good, wrench noted a stored fault code that the Head Unit may be faulty.

Well good excuse to get a new Head Unit with Navi and Bluetooth or even touch screen :-)

DRACO

Update, A week later, Sound is still good.

So wrench tells me Fuse 26, is the the hard reboot.

m1mmmm

Thanks Draco! Discovered speakers dead today and checked fuse 20 in trunk and noticed fuse prongs were grayish and after cleaning replaced fuse and have sound again. I have had my car since new and am thinking it would probably be a good idea to replace all these fuses since I'm sure they are all in the same condition. Thanks again for the tip!

DRACO

Cool, no need to replace, just remove and polish, corrosion creates too much resistance and cause havoc for the Sound System ECU due to drop in signal as the fuse is the weak point.

m1mmmm

Did you clean all your fuses? My car is going to be a keeper "weekend car" and has been exposed to high Texas temperatures since new so I want to eliminate as many future issues as possible. I was surprised at the amount of corrosion that had built up and I'm sure this was the first time that fuse had ever been out. Thanks, Mike.

DRACO

Yes, all my sound system components with emory cloth. I think there were like 3-4 fuses???

m1mmmm

But what about the rest of the fuses for the car? Wouldn't all our 10 year-old fuses have the same amount of corrosion? Or am I missing something? I guess I'm assuming if one fuse looked like that they all do. I'm not educated in electrical issues at all, just thinking about it in a practical manner.

DRACO

You have a good point. It would not hurt to check all the fuses.

On my 30+ yo 911 I replaced them all since they were all original :-o

Gultekin Gulsen

I took out and placed 64, 26, and 20 back in that order but it didn't work for me. Then I took 36 out (7.5 A ) and placed it back. And it worked!!

P.S. every time I took the fuses out, I turned the radio on without the fuses, turned it off, and placed the fuses and turned the radio on again.

Rudeney

Fuse 36 is for the AGW (audio gateway) module. Definitely should be one to check with audio issues.

TBlas

Here are my notes from my 2006 CLK350 convertible (W209) that was having the same issue:

4/17/2023
Issue: No Sound coming from speakers in FM mode or CD's.... all CD units stating No CD(s) in main unit or glove box CD Changer...yet there were CD's in all of them.
Pressing & Holding the "Eject CD" button for 10+ seconds didn't (initially) fix it during 1/2 hour ride home. Everything had been working fine on way to previous destination.
Tried turning car off, waiting 30+ seconds, then restarting....still not kicking audio back on : (

Fix: Waited til next morning. Still same issue as above. However, after pressing and holding the "Eject CD" button for 10+ seconds, it finally recognized and started playing CD after re-inserting it. FM radio started working again too : ) I guess some overnight patience paid off : ) : )

mcraec620@gmail

I'm going through the same thing right now I don't know if it's the CD changer but I have no sound I checked all the fuses and it's not that I don't know if it's the end but please let me know what you did might work for me
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