wywywywy

Hi all,

Basically I hadn't driven the car for a couple of weeks, and the batteries probably ran a bit low. It took much longer than usual to start and lots of warning lights were on, but after a blip of the throttle they were gone.

However, the COMMAND hasn't been right since.
- In navigation, it works but there is no sound
- In audio, it shows an empty radio station list, and memory card won't read
- In telephone, it shows a blank screen
- In video, it shows an empty TV station list

I have already tried reseting (then re-configuring), and I have also tried rebooting by holding the eject button. But they didn't solve the problem.

So what could it be? And how can I find out?

Dead secondary battery? (Possible)
Hard drive fault? (Unlikely because navigation works)
Antenna or antenna amplifier fault? (But GPS works)
Software corruption? (Unlikely because navigation works)
Amplifier? (Possible)
Audio tuner or TV tuner module? (Possible)

This is a 2007 W221 S Class with the Harman Kardon system.

Thanks.

gapcobenz

The HU in your car goes into "limp" mode if the battery voltage is not right. In this mode some of the HU functions work and others don't. Get both batteries up to speed by driving the car for an hour or so. If this doesn't cure the problem then.
1.You may need to update the telematics system at a dealer
2.The audiogateway (AGW) which is the amplifier,radio tuner and system controller could be defective. The AGW is prone to be damaged by moisture in many cases.
3.A combination of the above. Good luck.

wywywywy

Thanks for the info. I have already driven the car for about 10 miles on the motorway already.

So the audio gateway, am I right in saying it's in the left hand side of the boot?

Thanks.

gapcobenz

Correct,it's tucked away behind a metal panel top left corner. Check the TV tuner for moisture damage as well

wywywywy

Thank you. Do you by any chance have instructions to remove the trim panels by the way? I had a quick look but couldn't see all the fixing points. And I haven't been able to find it on Google.

gapcobenz

Remove floor mat. Side panels are made of moulded carpet if I'm correct. These just pull out with a bit of bending. There may be a few plastic push in clips that must be taken out.I'm not too sure about this, my apologies if I'm wrong.

wywywywy

Still haven't done anything because of the weather.

However, this morning it just started working again! I'm so confused! It still wasn't working as of last night.

Maybe there was moisture and now it dried up? Maybe the battery takes an extraordinary amount of time to charge? I just don't know...

I wish there was something like the VAGCOM for Mercedes.

gapcobenz

I've had this happen to some clients before. Some just work and some return with the same fault. The MB SDS cannot pickup the problem when the system is diagnosed, it only "sees" the fault when the component isn't working. The problem may lie in the HU or AGW. In both cases when this fault showed up again I reflashed the HU and AGW flash memory. No returns from the clients after that. In your case I hope the system keeps working.

wywywywy

Well it's playing up again

So looks like I'll need a new audio gateway, because I don't think I'll be able to get someone to re-flash the head unit and audio gateway in the UK, at least not anywhere near where I live.

Quick question - do the standard system and the Harman Kardon system have the audio gateway? I'm trying to source a second-hand one.

Thanks.

gapcobenz

In the W221 there is only one system, a Harman AGW. This is the standard system, there is no amplifier.The AGW model is a BE 7021.MB part # A221-870-7789/80. This is a service exchange unit from MB. I've checked and there is no Harman service centre in the UK. I suggest you have a MB dealership do a diagnostic test on your car before you buy anything. If the fault is present they'll be able to tell you which component in your car is causing the problem.

wywywywy

Thank you. Good point actually, as I don't think I will get charged just for getting a quote.

On the other hand, it briefly came back to life yesterday after loading/unloading a bunch of things in the boot... Weird thing. Maybe it's just a loose wire somewhere?

Digitalsleep

I have the same issue, i was wondering if you manage to get the issue resolved. would be great to get some details on how i should approach getting my command unit fixed.

thanks
-Digitalsleep

wywywywy

Not yet. Been busy with other things, haven't touched anything yet.

wywywywy

Just realised I had a typo in my last question. It should have been -

"Do the standard system and the Harman Kardon system have the SAME audio gateway?"

simon.handley

I am having the same problems as described in this thread. The car was formerly owned by my father, who has not reported any previous problems. However I have installed an PCMCIA card for MP3 music and I'm wondering if this is part of the issue. Will try removing the card and will report back. I'm not convinced, but it is worth a try.

Does anyone have a block diagram of the comand system or know where I can get one?

I have found this online manual download facility and wondered if anyone else had experience of using it?

http://www.emanualonline.com/Cars/Me...ce-Manual.html

Thanks

kgodfrey

I had this issue three weeks ago. The car was at the dealer for scheduled maintenance and when I picked it up I had symptoms identical to that of the original poster. Took dealer 48 hours but they eventually fixed it by replacing a fuse. Sadly I don't know which fuse....

ImInPA

A fuse would not likely be the culprit. I think your dealer experienced the unit working again and replaced the fuse to say they did something. A good fuse simply completes the circuit. If the symptoms are intermittent, a fuse cannot go bad then good. It sounds more like either a loose connection somewhere or a bad audio gateway. Good luck!

clinty44

hello all
My w221 s class 2007 radio sound stopped working after I brought the car back from the dealer after they carried out a repair of another fault (front parking sensors).
today the dealer has informed me that the amplifier is faulty.the cost of a new amplifier is over £1,150+labour=total of £1,645.00 to fix this problem.does any one know anybody in uk who fixes this fault.or where to get an amplifier from.my car has the harmann kardon sound system. please help urgently required.

wywywywy

I think these guys can do it but I have never used them so I don't know for sure.

http://www.commandonline.co.uk

wywywywy

Sorry just thinking about what you said there.

If DAS can't see (talk) to the unit, then how can it be reflashed?

And is online SCN coding needed to reflash these?

gapcobenz

The DAS system cannot reflash the AGW. Online SCN coding is also unable to reflash the unit.This is done with factory supplied equipment and software,in this case Harman Becker. From what I know there is no one in the UK that has this equipment. The nearest service centre for you would probably be someone in Germany.

Aj7393

Exactly the same problem. Parking sensor went in for repair and then suddenly no sound from the stereo... At a loss as what to do! Repair centre obviously saying nothing to do with them!

wywywywy

Many thanks for the answer. Really appreciate it.

wywywywy

There's a guy on eBay that's advertising a repair for this.

Has anyone used them?

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=321390148667

gapcobenz

The only authorized resellers are in fact Mercedes Benz dealers. Carefull what you buy without knowing the actual fault in the audio system. Have you had the system diagnosed by a dealer?