Now that I finally got my car fixed With all the bs it has to start with me again!! I'm driving down the road and all of sudden my radio goes blank then next time I start the car the cd player works then it turns off and says system unavailable now it keeps saying that and doesn't work at all. As I'm drivin it it seems as if it goes o power on itself the Mercedes logo come on and goes blank again. I tried researching on here an I tried the disconnecting the negative cable but came up with nothing. If anyone can help me out give me an idea of what it is or how I can figure it out any help is really appreciated. It is really boron driving down the road with nothing.

 

From your description, it soulds like there might be a break in your MOST ring... You said you finally got the car fixed, what was done to it?

It may also be a bad component on the MOST ring that is not passing the light of the fiber optic system through, thus causing the headunit not to power on.

 

just all lil bs stuff nothing with electrical or anything. i have the extended warranty but i refuse to bring it tpo mercedes since everytime it goes in it always comes back worse and something else is broken.. i just had my rear brakes done and they never said nothing about my shoes and i come to find out that theres no shoes left when they just did them 3,000 miles ago. just dumb things like that. and it does power on just says system unavaiable .. one thing i noticed is that it seems like the cd changer is going crazy in the trunk even when i turn the car off.. is there a way for me to diaganose the car to figure out what it is? also if its the ring like you said how much is it to replace? is it something i can do myself?

 

+1 MOST

 

I see the diagram but how is this supposed to help me and how would i test it to see where i guess there would be a break in the signal or whatever.. any idea of how much something like this would cost to fix?

 

Weird, mine did almost exactly the same thing today. iPod started skipping, it'd randomly change to radio and then CD, and now the audio works again but NAV & MAP say "Navigation Device Unavailable". Dropped it off at the dealership already.

 

How much would it cost? should be covered under warranty, if not and you want to attempt to diagnose it.
start here,
http://www.startekinfo.com/StarTek/

 

Not trying to be cheap but if I'm gonna pay for that I might As well bright it to the dealer since it costs about the same for an hr diagnostic fee and that. Thought there might be a way to pull a code out of it or something.

 

Check all your fuses for the components on the most ring. I had a changer fuse go out and all I got was the star logo and then nothing. Found the changer fuse had blown. Replaced and was good to go. No more problems since.

 

Does anyone know where it would bbon my car 05cl55

 

Not sure what "bbon" (be on I guess) means but the fuse for the changer is on the driver side dash panel where the door meets the dash. There is a piece of paper under the panel that shows you which fuse is for what. I believe it's fuse number 7 but cannot be 100% sure. Just check the diagram.

 

Thanks I'll do that as soon as I get home. The cd changer is going crazy though when I went in the trunk after the car is off don't thinkbit usually does that. Also some one told me tere is a recall in the compass or something that they have to replace the head unit for free?? Anyone hear of this being an issue or even that it's a tsb?

 

WOW take it to a dealer, if you can't find the fuse after I posted the StarTek link, you are getting in way over your ability.
Don't take this advise in the wrong way.

 

I Went on the site on my phone and u have to pay to use it if I was gonna pay that much to try and figure it out on my own then I would take it to the dealer. I know where the fus panel is I wanted to know if someone could tell me what fuses to look for. I have built cars before I'm sure I can handle a fuse. Never had An issue like this before and I refuse to go to the stealership.

 

From what you have described, it really does sound like there is a break in your most ring...

MOST - Media Oriented System Transport - Most high end vehicles use either a most bus, or a very similar system to carry audio and video signals throughout the car...

I will do my best to explain this to you as easily as possible...

Your headunit has very few wires plugged into it, this is because there are many other devices it talks to in order to function. Your headunit sends and receives signals via fiber optic cables. Through this fiber optic cable, your headunit sends a signal to your cd changer (if equipped) ... Your cd changer will process the signal, and then send it to the Voice Control Hands Free unit. Again, that module will process the signal, and then send it to the next device in line, the SDAR unit... That will process and send to CP, and the CP will process and send to your Navigation Computer. The Navi computer will send to your AGW (amplifier) and finally, the amplifier will send the signal back to the headunit...

That is the ring. The signal has to exit the headunit, travel through all modules via fiber optics, and then return into the headunit. Sometimes you can accidently pinch a wire while doing work to your vehicle. This is rare if you havn't touched anything in the vehicle. What is more likely is that a certain module is failing, and no longer passing the fiber optic signal to the next device...

For example, if your navigation computer was faulty, it would receive the signal from the CP module, but not send anything to the AGW module. In return, the AGW module would not receive a signal, nor send anything to the headunit. If the headunit doesn't receive a signal back, it won't power on, thus signaling a "break" in your most ring...

If you go to the dealer, you can buy something called a "most jumper" which is just a little plug that will help diagnose a failing component. For example, let's say you are suspicious that your cd changer is faulty. You would buy that most jumper. You would remove the fiber optic connector from the cd changer, and plug that connector into the jumper. The jumper will then complete that particular ring and help diagnose if the cd changer was at fault, or not...

If you havn't worked on a MOST system before, now is not the time to start... This isn't your typical stereo, and some components even require dealer programming when replaced.

I hope this helped shed some light as to what is hapening... Take a look at the picture Yacht Master posted. It will help visually describe what I just told you...

Good Luck! Also, if you do have warranty, you might as well take it to the dealer.

 

Thanks for the help. I understand why your saying. I took the fuses out under the hood f23, f24, f25. Car audio system cd changer and sound system. Now that I took them put waited 10 mins and put fuses back in I have no power at all to the radio. Does this help figure it out or any ideas how that could of now happened?... Apparently my warranty expired and I didn't even realized called my service advisor before and it just expired apparently.

 

I just started my car again and the system starts up but same system still says system unavailable. I did notice it is not showing the cd changer on the screen and like I said before the cd changer is ground crazy in the trunk. Does this help for anyone to ve able to tell me what it is?

 

Hmm... where's the best place to get a Navi DVD? Can they be burned? Dealer replaced my nav but took the DVD with it... It doesn't need to be current.

 

don't know how this has anything to do with the thread but check the for sale section or ebay.

 

Speak with the service manager they may approve a goodwill repair since warranty only recently expired. If refused, request to speak with the MBUSA rep covering dealership to approve repair.

 

I just took out the bose amplifier.. i disconnected the fiber optic cable and is was flashing which supposably means that the head unit is sending the signal is there a way to tell other than that if it def the amp.. plus it happened to possibly get wet.. did i find my problem?

 

usually when a dealer replaced a navi computer, they have to give you either the same, or a new map disc... you may want to go back and consult with them...

be careful with the fiber optic connector for your bose amplifier... the smallest amount of dust can hurt the amount of light that passes through... if your amplifier got wet, it's safe to assume that it's the culprit... buy a most bus jumper and attach it to the connector for the amp. see if your headunit will turn on once you do that...

 

where can i get one of those from.. i also tried the head unit again after disconnecting the amp and the same issue it turns on says system unavailable and then turns off...does anyone know the exact route on my car to how the fiber optic system goes. i'm assuming that if i went through the cd changer nav etc with that jumper that if one of them plugged in the jumper makes it work again that the issue is that component. any other way to check it just to ake sure i am right before i attempt to buy a new amp.

 

any one know of there i can get a bus jumper or any other way to eliminate what it could be?

 

Ebay. Which one do you need?