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Old Feb 12, 2026 | 09:04 AM
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Mercedes s212
Exclamation S/ W212 speaker noise issue

The left rear door speaker have suddenly started to give a clicking/sparkling noises from my s212 (e class 2012). Have tried to capture the noise in the attached video where the clicking noise comes and goes. Does anyone have experience with what this could be caused by? Speaker fault, wiring fault, amplifier issue, etc? Thanks for your help!
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Old Feb 12, 2026 | 10:16 AM
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W212 E63S Wagon - GSL580 - E63 - E350 - C300
Heh - when mine did that the pass-rear ended up shorting out, melting the wires and filling the car with smoke. This was like two years ago...I fixed it last week.
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Old Feb 12, 2026 | 12:21 PM
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Originally Posted by Bias
The left rear door speaker have suddenly started to give a clicking/sparkling noises from my s212 (e class 2012). Have tried to capture the noise in the attached video where the clicking noise comes and goes. Does anyone have experience with what this could be caused by? Speaker fault, wiring fault, amplifier issue, etc? Thanks for your help!
https://youtube.com/shorts/D2y6i40_rzY?feature=share
this is caused by the main audio amplifier built with under rated 16V capacitors in 14.9V cars.

The amp sends DC pulses into the fragile speaker voice-coil... smokes the wire insulation by cooking it.

New Amp + new speaker... setup for a repeat!
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Old Feb 12, 2026 | 02:55 PM
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Originally Posted by OldManAndHisCar
Heh - when mine did that the pass-rear ended up shorting out, melting the wires and filling the car with smoke. This was like two years ago...I fixed it last week.
oh, that sounds bad. How did you fix it? New amp and new speakers?
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Old Feb 12, 2026 | 03:00 PM
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Originally Posted by CaliBenzDriver
this is caused by the main audio amplifier built with under rated 16V capacitors in 14.9V cars.

The amp sends DC pulses into the fragile speaker voice-coil... smokes the wire insulation by cooking it.

New Amp + new speaker... setup for a repeat!
Was worried about that after reading some other cases, but thought that was mainly a issue for the facelift/ 2014 models. Any idea if the amplifier is hard do change?
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Old Feb 12, 2026 | 03:07 PM
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Originally Posted by Bias
Was worried about that after reading some other cases, but thought that was mainly a issue for the facelift/ 2014 models. Any idea if the amplifier is hard do change?
the labor is a 10mn simple swap.

If coding is needed forum sponsor @BenzNinja can provide his remote coding services.
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Old Feb 13, 2026 | 07:54 AM
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From: Fleriduh
W212 E63S Wagon - GSL580 - E63 - E350 - C300
Originally Posted by Bias
oh, that sounds bad. How did you fix it? New amp and new speakers?

I found a new (used) speaker from a junk yard. Had to replace some of the wires as they melted together. One would not think a STOCK sound system would do this....Heck, I dont even listen too loud, it is generally talk radio (dont forget, I am old)
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Old Feb 15, 2026 | 04:58 AM
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Originally Posted by CaliBenzDriver
the labor is a 10mn simple swap.

If coding is needed forum sponsor @BenzNinja can provide his remote coding services.
Any idea where the amplifier is located in a s212 2012 model? Do not have harmon karbon, only standard speakers. Checked the sides of the trunk and did not find it.
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Old Feb 15, 2026 | 11:54 AM
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Originally Posted by Bias
Any idea where the amplifier is located in a s212 2012 model? Do not have harmon karbon, only standard speakers. Checked the sides of the trunk and did not find it.
If it's not located on the rear sides then see what's under trunk floor area?
When you open these sections inspect/clean the shared GND posts.
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Old Feb 18, 2026 | 12:18 PM
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Similar but more severe experience... Crackling noise, acerbic smell followed by smoke emanating from the top dashboard in the middle, which didn't stop with ignition off. Towed to dealership... no codes... replaced speaker for $736. A few months later, same experience... Believe it is a deficient amp design. Keep looking for recall or class-action suit. -- Suffice it to say, this will be our last MB.
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Old Feb 18, 2026 | 05:53 PM
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performs as designed

Originally Posted by MB-Ned
Similar but more severe experience... Crackling noise, acerbic smell followed by smoke emanating from the top dashboard in the middle, which didn't stop with ignition off. Towed to dealership... no codes... replaced speaker for $736. A few months later, same experience... Believe it is a deficient amp design. Keep looking for recall or class-action suit. -- Suffice it to say, this will be our last MB.
The audio Amp is carefully built with 16Volt parts on a 15Volt chassis. Using a 1Volt margin is a stressful environment. Using a 30Volt part would cost the same without any problem.

That's the fix here to undo this productive setup.
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Old Feb 20, 2026 | 11:27 AM
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Do we all need to replace our amplifier?

Originally Posted by Bias
oh, that sounds bad. How did you fix it? New amp and new speakers?
I’m very curious now to know if we should replace our amplifier? My 2014 E350 Sport isn’t making these noises, but it sounds like a serious concern. Any recommendations on what kind of amplifier we should use for the replacement
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Old Feb 20, 2026 | 01:12 PM
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Originally Posted by jjE350
I’m very curious now to know if we should replace our amplifier? My 2014 E350 Sport isn’t making these noises, but it sounds like a serious concern. Any recommendations on what kind of amplifier we should use for the replacement
My car have standard speakers, not the Harmon Kardon speakers. So found out that the amplifier is built in the audio system, which is supposedly not common to fail. Will therefore first try to replace the speaker and see if that solves the issue.
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Old Feb 20, 2026 | 04:05 PM
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From: Marshfield, Missouri
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Originally Posted by Bias
My car have standard speakers, not the Harmon Kardon speakers. So found out that the amplifier is built in the audio system, which is supposedly not common to fail. Will therefore first try to replace the speaker and see if that solves the issue.
My car does have the Harmon Kardon system, so do you know if the amplifier is located in a different location
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Old Feb 21, 2026 | 12:12 AM
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Originally Posted by jjE350
My car does have the Harmon Kardon system, so do you know if the amplifier is located in a different location
For the HK setup the amplifier should be located in the boot, usually on the left side behind the polstring.
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Old Feb 21, 2026 | 11:19 AM
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From: Marshfield, Missouri
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Originally Posted by Bias
For the HK setup the amplifier should be located in the boot, usually on the left side behind the polstring.
Thanks for the info, I appreciate it
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Old Mar 1, 2026 | 02:06 PM
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Hi, I'm actually dealing with this right now too. I have the HK system and my driver side door tweeter started smoking and making loud buzzing sounds while driving. One of the speaker contacts looked burnt(not the wire connection). The amp has made buzzing sounds in the past(like 3 times in the past year). I purchased a new speaker and amp off ebay. I installed both yesterday(its easy) but I do not have sound. Not sure if the new/old amp is actually defective or what. Not sure if coding or fuse resets are needed. Some have said there is a way to bypass the amp but im still looking for that. I would love some help too!

On another note. I have had HK tuners/amps for my home entertainment set up in the past and they did the same thing! I love the sound these put out but the components do not last...

2016 E350 sport
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Old Mar 1, 2026 | 03:07 PM
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Originally Posted by CaliBenzDriver
The audio Amp is carefully built with 16Volt parts on a 15Volt chassis. Using a 1Volt margin is a stressful environment. Using a 30Volt part would cost the same without any problem.

That's the fix here to undo this productive setup.
Hi, do you have the link to upgrade/fix these amp? Im interested in preventative fix, upgrade the amp with more proper capacitors. Thank you
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Old Mar 1, 2026 | 06:17 PM
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Sound amplifiers weaknesses

Originally Posted by nguyenphananh
Hi, do you have the link to upgrade/fix these amp? Im interested in preventative fix, upgrade the amp with more proper capacitors. Thank you
Navigate the link in my signature... Audio Amps are in there towards the end.

This will take a couple cheap caps + thermal paste... $5 top.

> BEFORE/AFTER...
Use a DVM or scope to confirm DC voltage is frying speakers. Voice coils move only with AC, never any DC current.
Don't just plug in new speakers without testing.

Each speaker channel is powered by an individual IC chip channel (couple channels per chip).

This setup is unlike traditional amps, there is no pass-band filter working from only 4+1 channels.
Here we have countless channels with direct connection to each spk voice coils.

Last edited by CaliBenzDriver; Mar 1, 2026 at 08:55 PM.
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Old Mar 12, 2026 | 01:11 PM
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slk280
Originally Posted by CaliBenzDriver
Navigate the link in my signature... Audio Amps are in there towards the end.

This will take a couple cheap caps + thermal paste... $5 top.

> BEFORE/AFTER...
Use a DVM or scope to confirm DC voltage is frying speakers. Voice coils move only with AC, never any DC current.
Don't just plug in new speakers without testing.

Each speaker channel is powered by an individual IC chip channel (couple channels per chip).

This setup is unlike traditional amps, there is no pass-band filter working from only 4+1 channels.
Here we have countless channels with direct connection to each spk voice coils.
Hi CaliBenz
I finally have time to go over and read up your post. From your signature, I found this link.
https://mbworld.org/forums/e-class-w...-siblings.html

I read through most of the mods, but couldnt find the specific thread regarding Audio Amp capacitors upgrade. Can you please post the link to this specific mod. Thank you
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Old Mar 12, 2026 | 01:39 PM
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Originally Posted by nguyenphananh
Hi CaliBenz
I finally have time to go over and read up your post. From your signature, I found this link.
https://mbworld.org/forums/e-class-w...-siblings.html

I read through most of the mods, but couldnt find the specific thread regarding Audio Amp capacitors upgrade. Can you please post the link to this specific mod. Thank you
You're likely better than me at searching the MBW forum - Trust me on that

You're looking at replacing 16V caps + dry heatsink compound - Do you need to troubleshoot any dead channel Ic??

We used to be able edit posts to organize INDEXED CONTENT... this has been disabled

German diesel-electric engines
German heavy oil diesel-electric engines
I'm a bit tied up roaming with friends & family


Last edited by CaliBenzDriver; Mar 12, 2026 at 01:46 PM.
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Old Mar 12, 2026 | 02:22 PM
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Originally Posted by CaliBenzDriver
You're likely better than me at searching the MBW forum - Trust me on that

You're looking at replacing 16V caps + dry heatsink compound - Do you need to troubleshoot any dead channel Ic??

We used to be able edit posts to organize INDEXED CONTENT... this has been disabled

German diesel-electric engines
German heavy oil diesel-electric engines
I'm a bit tied up roaming with friends & family
"MBW"??... do you meant BMW?? I recently acquired the 2016 W212 few months ago. Nothing wrong with the audio system yet, I just wanted to preventative upgrade these components to prevent future break down. Last time I followed your guide and upgraded (solder) the keyless entry PCB board, it worked wonderful, solved the "replace key battery" issue for good. Im good at following instruction. If I can find that link/instruction, I will do this mod.
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Old Mar 12, 2026 | 03:04 PM
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GOOD AMP GREATER

Originally Posted by nguyenphananh
"MBW"??... do you meant BMW??
I recently acquired the 2016 W212 few months ago. Nothing wrong with the audio system yet, I just wanted to preventative upgrade these components to prevent future break down.
Last time I followed your guide and upgraded (solder) the keyless entry PCB board, it worked wonderful, solved the "replace key battery" issue for good.
I'm good at following instruction. If I can find that link/instruction, I will do this mod.
MBW forum is "MB World dot org"

Being early should avoid the voice coil cook-out experience.
No troubleshooting dead channels without the proprietary schematic makes for NO headache.

Caps upgrade + heatsink rework to smooth out metal bumps in the matting surfaces = *HOT* Chips! (ie. built-in factory defect).

-- If you have your chassis WIS diagram:
- then locate ALL the Amp GND sources
- else simply clean the trunk shared GND Posts around trunk area
while all batteries disconnected.

This step will provide less glitches in the Amp power feed under high output. Filtering Caps get an cooler life with CLEAN Power + GND!!

Divers heaven 30+ drift dive sights
Divers heaven 30+ drift dive sights

> NUGGET: Sleepy Fan!
Amp does have a built-in cooling fan but when little heat gets transferred into the heatsink mass, the fan does not sense heat needs cooling.



Last edited by CaliBenzDriver; Mar 12, 2026 at 05:43 PM.
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Old Mar 14, 2026 | 11:31 PM
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Originally Posted by CaliBenzDriver
MBW forum is "MB World dot org"

Being early should avoid the voice coil cook-out experience.
No troubleshooting dead channels without the proprietary schematic makes for NO headache.

Caps upgrade + heatsink rework to smooth out metal bumps in the matting surfaces = *HOT* Chips! (ie. built-in factory defect).

-- If you have your chassis WIS diagram:
- then locate ALL the Amp GND sources
- else simply clean the trunk shared GND Posts around trunk area
while all batteries disconnected.

This step will provide less glitches in the Amp power feed under high output. Filtering Caps get an cooler life with CLEAN Power + GND!!

Divers heaven 30+ drift dive sights
Divers heaven 30+ drift dive sights

> NUGGET: Sleepy Fan!
Amp does have a built-in cooling fan but when little heat gets transferred into the heatsink mass, the fan does not sense heat needs cooling.
Hi, I did a search on this site, read bunches of thread, but didnt find much information regarding upgrading the amplifier. I found this thread with 1 post, just 1 post, with picture and mentioned of upgrading the amp. However, it did not say much regarding the replacement capacitors. Can you post the specs for these capacitors? I know they are usually Nichicon, 16V... but that about it, no capacity, resistan...etc. I want to order these parts 1st before disassemble the amp. Also any other upgrade for this PCb? should I put a heat sink on each of the hot IC chip? specific part number?. This is the link to your post , the information was very limited...

https://mbworld.org/forums/e-class-w...r-upgrade.html
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Old Mar 15, 2026 | 12:59 AM
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DEBUGGING AUDIO AMP

Originally Posted by nguyenphananh
Hi, I did a search on this site, read bunches of thread, but didnt find much information regarding upgrading the amplifier. I found this thread with 1 post, just 1 post, with picture and mentioned of upgrading the amp. However, it did not say much regarding the replacement capacitors. Can you post the specs for these capacitors? I know they are usually Nichicon, 16V... but that about it, no capacity, resistan...etc. I want to order these parts 1st before disassemble the amp. Also any other upgrade for this PCb? should I put a heat sink on each of the hot IC chip? specific part number?. This is the link to your post , the information was very limited...

https://mbworld.org/forums/e-class-w...r-upgrade.html
there are couple threads to deal with the digital HK audio amplifier.
-- A: integrated digital fiber to analog amplifier -- B: power supply filters
-- A: integrated digital fiber to analog amplifier -- B: power supply filters

-- A - HOT IC CHIPS:
We have a 5 chips count used to pump audio current through each speaker voice coil beside the rear deck separate woofer.

As mentioned earlier the heat is transferred by contact between the chips and the enclosure that is the heatsink itself.

Do remove/collect (save?) the heatsink white silicon grease
then inspect and polish smooth the contact surface on the heatsink side the same way it is on the chip side. Zero aluminum surface bump is tolerable.
Notice that all chips are soldered to the board, any one single heatsink bump imperfection raises ALL THE CHIPS away from heatsink, not only one!!
You want to ensure maximum heat transfer. Spend an hour filing and polishing. Keep metal fillings away from electronic board.

(Lastly reapply thermal compound new or reused before final assembly after replacing caps)

-- B - POWER FILTRATION CAPS:
The 3x 16V caps are 3300uF each in parallel for a total of 9900uF filtration.

You want to bump that to a safer 25V (or 35V standard values) - The issue is the capacitor physical size versus what room is available.

The result does not need to be pretty... lay down caps glued on their side is fine. Needless to say what the pins polarity (+/-)

> HOW...:
-- You best need to first open up the Amp to workout what caps you're going to buy.

-- You can try to bump up the 3300uF to a higher filtration... 4700uF Ea ?

-- You can try to use "LOW ESR" caps to filter the high frequency noise inflicted by the nearby 3-Phase fuel pump module.

-- So more voltage, more capacity with lower serial resistance that still fit inside.

The key here is your proprietary chips are not blown up so it's an easy job, take your time.


Last edited by CaliBenzDriver; Mar 15, 2026 at 01:10 AM.
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