Mercedes ML500 (W164) 2005 Comand NTG - Harmon Kardon Amplified Audio system, No sound or comand unit boot up - stuck on Mercedes Logo diagnosed & Fixed
Great explanation. Thank you. I have lost sound from my gl450 2007. The radio/cd turn on and appear to be working but no sound. Checked the amp--it looked good. No water damage anywhere. So it must be one of these modules.
I had this very problem. It has been annoying me for months, looking for a replacement command unit, until I finally found one. Plugged it in and same problem. I did not know about the phone module. Then, by accident, I found your video and yes my issue was the phone module gone bad. All good now. Thank you.
@@zondi27 my problem was due to the phone module that is linked into the optical system. It's located underneath the rear seats. It needs an optical bridge to test and replace the module. As on ebay.
Hi everyone, thanks for your kind comments. A Common question that comes about is regarding the Fibre optic shunt tool (bypass cable) also the name of the item they should search for? These items are very much available at a very cheap price from eBay and many other onliine sellers. Try perhaps on eBay e.g. typing "MOST Fibre optic shunt" or "MOST Fibre optic loop bypass cable" These items are an essential item for your tool box for testing and eliminating many issues for Mercedes, BMW, Jaguar / Range Rover, Audi and many other vehicles that Run on the M.O.S.T optic platform. Earlier Mercedes (Pre 2001-4) run on the older D2B Fibre Optic format, completely different to M.O.S.T. but principally the same method to loop out and diagnose a faulty component. For those that are confused how on earth this complex system works? Imagine each component (Module) on your vehicle that makes up the complex audio system and much more. Try to liken this system as if it were like a central heating system, a system with ten or more water fed radiators that all have to work as a team to feed heat and water through them to complete the chain. You block or remove one radiator, the rest are starved and the rest of the system cannot work as the one behind cannot feed with water (in this case optic data) similar to why only half your Christmas lights work and the rest are out!? MOST Fibre optic system is very similar, it is a process of elimination, one of which you will need to know exactly the spec of your vehicle and what components you have to make the system on your particular vehicle. Imagine the audio head unit (or Comand unit) on your Mercedes is the engine, or rather the boiler pump, this unit will distribute audio and other data to other components, optic signal in, optic signal out to another component, optic signal in & optic signal out & so on to the next component (same as central heating radiators) water feed in, then the return feed out and so on. As you saw in this video I made with this particular Mercedes ML the component that was at fault was the Cellular Phone comms unit, when any of the coponents that make up the important chain become faulty or fail for what ever reason, they will break this imoprtant chain and will starve the other important components down the line, yes ultimately the audio amplifier (that is usually last in the chain) Some obvious item to check - test - eliminate from the system (with experience) are. DVD - CD Rom Navigation units, Multi CD - CDC changer units (E class and CLS mounted below audio head unit- usaully motorised) any outher units such as emergencency cellular location device modules, Cell phone HF modules, any one of thes could be the issue for thew failiure of you audio system, everyone will first assume the audio amplifier or gateway module, no not very often unless the vehicle has suffered extreme water ingress or flood damage - then anything or more than one component could be the culprit! For example, Range Rover L322 2005 onward have same issues, usually the Nokia Bluetooth HF Module mounted in the boot fails, this will F@ck up the whole system, or the glove box mounted CDC (CD Changer unit) Eliminate this with the shunt tool and whole system comes back to life! Best of luck with this knowledge and really hope it is of help to you all!
great video and explanation there will be 8 yr olds fixing merc audi stereo systems before we know it lol . i have had an issue with the module and motor that control the automatic tail gate opener do you think this cauld be the issue?
I am having a similar issue. The Mercedes logo is stuck on display. I can insert a cd and it will play but nothing else. The screen just stays stuck on the logo. No radio, no Navi none of the buttons work except the eject button. The volume buttons and the arrows buttons on steering wheel are not working. I do have volume when playing cd
Great video. The volume buttons on the steering wheel on my ML work, but not the volume knob on the radio. What would you think may be the cause in this case. Thanks.
My 2006 Mercedes CLK350 has a similar problem- I put in a DVD in the Navigator cd player and it got stuck. Now I have nothing but hope I can repair it.
Can you help out ? I can't locate the actual module for the audio/navigation/CD system in my C350 - 2006. I have a problem with my audio system as it keeps switching off. I noticed many have similar problems & they fibreloop it. I looked in the boot & under the rear seat & found nothing. Is there a link to the diagram ?
Hello and thank you in advance for your answer :) I have the same problem with my ML 320CDI-06 and am curious if bridging with this cable will restore all functions on the APS COMAND (navigation, rear view camera, CD changer). ) and I can be used, or does the radio only work again?
My command unit gets stuck on the boot screen, and I know it's the Navigation unit. Where is the MOST connector for that located ? I'd like to add a bypass loop onto it. Thanks !
Hello, I have the same car and the same problem, I have put the cable but I still have the same problem that it turns off by itself, what else can I do?
Hi, the problem could be the amplifier that has failed, amp situated under the passenger seat (UK) vehicles, you could try capping the amp out of circuit, if it solves the command unit non booting issue you have no sound but you will know its the amp thats at fault, or something else on the fibre optic MOST ring
I keep them for use in the workshop for Mercedes, Bmw, Range Rover, Audi, Porsche etc, I keep the unused parts when I install Dension Gateway etc, they are available on eBay I'm sure
