Turned on the ignition yesterday and the radio was not working.  Hearing a clicking, whistling sound even when car is turned off.

Hope someone can help.



Does the radio turn on but you hear no sound? Or does it not turn on at all?

Eva, 2018-10-17

Hi, no, it does not turn on at all, but I hear a clicking and whistling sound even with the ignition off.


That may be the noise coming from the CD changer, which is normal. Maybe you never paid attention to it before.

I would start by checking the fuses for the COMAND unit.

If the fuses are good, you most likeley need a new head unit. You can test, verify that with a Star Scanner that the dealer and Mercedes mechanics use.

Eva, 2018-10-17

Thank you so much! Do you know where the fuses are located for this year and model?

Eva, 2018-10-18

Thank you! Appreciate your time and advice.  My car only has 40,000 miles. Hope it’s not the hole unit.  What would that cost?

Eva, 2018-10-18

Help!  Just went to start the car and the battery is dead!

If your car died and with the problems you are experinceing there is a very good chance that the Audio Gateway Module (AGW) is bad. It controls your audio system. If it goes bad it will drain your battery. Now in addition to the COMAND you need to look at the AGW as well. These systems can be tested with Star Diagnostics. In the mean time, if you don't want your battery to keep dying when you park the car, you may want to remove the AGW fuse. When you take the car in for repair, you should let the shop know that AGW fuse is removed.

At this point what I would recommend is take the car in to a shop that specilizes on MB cars. Have them diagnose the problem wich will run you about $100 - $130. Then you can decide if you want to replace the part yourself or not. Also don't waste time taking it to any repair shop. Take it to the dealer or someone who works on MB all day.

Eva, 2018-10-18

Thank you MBFanatic  for all your advice.  I’ve dropped it off and they will test with Star diagnostics.  I had a 99 ML 320 for 12 years.  Not complicated like this one.

Eva, 2018-10-19

Just found out it needs a new Command unit which costs $2,250 without labor!  This is absurd.  There must be something else.  I’m thinking of call MB headquarters.

You may want to consider getting a used one and having an indpended mechanic install it for you. A used COMMAND runs around $350-$500. Plus $200 or so to install and program. Much cheaper than going to the dealer.

Or there is an even better solution: An aftermarket head unit. They run on Android, come with navigation, Bluetooth and a lot of cool features. You may need to have a shop install it.

This is what I am talking about: Android 7.1 Car DVD GPS Navigation for Mercedes Benz ML W164 GL X164

One thing to keep in mind is that you may loose the function of the steering wheel buttons. Look in the description because it will tell if your steering wheel buttons will work or not.

Eva, 2018-10-21

Thank you MBFanatic.  I’m checking the links you sent.  Appreciate your time and advice,


I would look at the Audio Gate Way module first. That could be the problem. It can drain your battery and it can also prevent the COMAND from working properly. A used one can be used. 

Eva, 2018-11-09

Hi, not finding any help getting a new command unit.

Is there somewhere where they refurbish these units?  My paperwork from the diagnostic test says Head unit S 164 900 73 01 80.

Any help in finding one would be greatly appreciated.



I would check ebay. A lot of used units and you may be able to get a refurbished unit there as well.

I am glad to listen this positive approach to deal this issue. Hope you will never have it again.

Thanks for visiting this always helping website. Keep posting your questions.

The main fuse box is located in the engine compartment on  driver’s side. Auxiliary fuse box is located inside the cabin, in the passenger foot well

I would have an audio shop install that headunit. 


What does that have to do with anything discussed here? 

Plain text

  • Allowed HTML tags: <a href hreflang> <em> <strong> <cite> <blockquote cite> <code> <ul type> <ol start type='1 A I'> <li> <dl> <dt> <dd> <h2 id='jump-*'> <h3 id> <h4 id> <h5 id> <h6 id>
  • No HTML tags allowed.
  • Lines and paragraphs break automatically.
  • Only images hosted on this site may be used in <img> tags.
The content of this field is kept private and will not be shown publicly.

Disclaimer: Youcanic has made every effort to assure the accuracy of the information on this page. Neither Youcanic nor its affiliates assume responsibility for any loss or damage due to any errors, omissions, lack of information. You agree to hold Youcanic free from any liability arising out of the use of any information contained within. All pictures and references to trademarks and car names are for reference only and do not imply an association with the manufacturer. Consult your owner's manual or authorized factory manuals when performing repair procedures. By entering this site, you agree to our Terms & Conditions and Privacy Polity.