Hardthur

Hello everyone
I have just purchased a late late 2002 Mercedes S320 CDI facelift.
Great car, high mileage (210k miles!) and works well.
I have the standard audio system that I find quite okay for the era. Just need to crank up the bass and treble to have a decent audio. (i prefer the standard system in my w204)
However, at random times the audio cuts off for 2-3 minutes and then works back.
I noticed that this happens most frequently when I drive uphill. Let's say this is just an hypothesis, not quite sure yet if that's the main cause.
But, during long trips, this issue happens only at the beginning. I drove for 2h20 this morning and for the first 20-30 minutes the audio was buggy (cuts off every second for 3 minutes) but after that everything was fine.
This issue happens also, at the same time, with the radio and CD. (I use auxiliary source)

Has anyone experienced this ? My takes are :
1. There are bad cabling from the COMAND to the Speakers
2. A battery /auxiliary would need replacement ?
3. Mercedes' take is : there might be a cable near one speaker that is connected to the ground of the vehicle and that could cut off all sound.
4. COMAND system is simply dying It seems to be in really good shape though (especially the screen itself)

Furthermore, Mercedes diagnosed my car because I wanted a major inspection. According to them, there were no codes regarding the COMAND system.
The only relevant codes were about the parking sensors.
My S320 is equipped with Parktronic (front and back sensors). The major problem with them is that when I turn them on, there's a two second solid beep and two red lines. Then they shut off.
The codes mentioned that there would be 3 front sensors dead but Mercedes don't believe so. They believe it would be the cables of the sensors themselves that could be twisted / damaged.
According to them, 3 sensors could not break this easily. 1 is a possibility, but not 3.

Has any of these two issues happened to you ? Would you have any tips ? I believe these issues can also occur with W210/W211 E Classes right ?
Looking forward to hearing from you guys

Have a good day

e350forme

first thing about radio problem I would check the drivers side rear wheel well where the radio amp sits, and I bet you there is moisture/water there

otherwise I have no idea.

amps are cheap replacement. same with the COMAND

e350forme

honestly w210 and w211 have nothing in common except the transmission right, the 5 speed

tim687

I think you should try and to a loopback test of the D2B loop. If the fiber cable is kincked sound could cut-off now and then, especially when it seems to cut-off when driving uphill.

As for the parktronic system, I'm not sure. You could try to swap a few sensors around, to check if the codes come along, but it could also be the control module.
I know that they are a little sensitive to moisture. When I recently washed my car, a few of them stopped working until they where completely dry again

Hardthur

As I have the base sound system, is there really an amplifier ? I can't seem to find that info on the internet. I only find that there's the bose amp in the trunk (in case you have the bose sound system ofc)

tim687

Hmm

Do you have a CD changer?
Have you tried to read out the fault codes using COMAND itself?

Google around on COMAND 2.5D diagnostic procedures

Hardthur

Yes I do have a cd changer in the trunk but I've never tested it. It seems to be detected by COMAND though.
No I haven't tried to read the fault codes with the COMAND, I didn't even know it was possible. I tried googling that but it seems quite hard to find useful information.

Would you have any website or videos that could teach me how to do this ?
Thanks a lot

Hardthur

Hello, after browsing the internet for some time I finally found how to access diag mode with my facelift COMAND.
I select aux source and press simultaneously mute, 1 and 3.

I got 5 error codes that were in "P" state. I checked on "mercupgrades" their meaning, they seemed quite bad.
I pressed Mute + 0 to wipe them and now I'll check if my issue happens again (which is likely). Then, i'll check the error codes that this will generate and i'll keep you informed

e350forme

Not sure why no one has told you yet, yes it has an amp go check it out. is the well wet? if so you need a new amp. otherwise it is easy to dig out the carpet to see all of this. 8mm ratchet for the cradles for each thing like cd player, amp and there is another box there for something else