The dreaded HK amplifier :(:(:( Pretty sure its had it?

[Submariner1]

took the moggie to the vet yesterday and had the stereo on pretty gently ‘cos of his teeney weeney ears ... and all sounded perfect. Arrived home turned off car, opened door and the stereo turned off as it should.

Went to get some smokes today ..... and a horrible pretty loud scratch sound something like music came from the passenger door tweeter. The rest of the system seemed mute.

Quick synopsis.
Left side tweeter seems disproportionately loud and incredibly scratchy, if you turn it up you can just about hear the mids and base notes in the left door.
The right side sounds virtually dead, maybe the faintest of sounds.
Turn it up lots and you can hear the bass but its not perfect..

Moving the surround sound around doesn't seem to work properly.

You get this effect on tne radio and the cd and even the blasted sat nav.
Turned the engine off 3 times its still there!
Turned off the Audio and baxk on ... and still there!

The only thing done to the electrics recently
Added a piggy back to the rear cigar lighter, and I did take out the rear centre upright boot liner. And added an earth point by putting one of those rings on an existing protruding stud.

But everything had worked fine for a week after that.
Whenever aincharge the battery with the mild CTEK 3.5 amps max. I always turn tne car off and turn off Comand before starting the charge.

Its as though the right channel has completely gone and more volume is directed to the left tweeter with a very faint signal to the left mid range.

If I was incredibly lucky I suppose the tweeter could be shorting on the left side, but thats illogical as
that wouldnt effect the right side channel?

In light of all the crap I have read about HK, and shes nearly 9 years old, it sounds awfully like the HK Amp has crapped out.

Too depressed to think logically about this. Only 42,000 miles and the Amp is shot!

1.where does one start?
2.where would they place the HK amp in a C216?
3. When people have trouble with these amps, does the sound normally go totally?
4.would the iCarsoft MBII pinpoint this ? And Or give fault codes for the dumbf@ck MOST / Canbus system this unit possibly works on?

I have turned off the audio, just in case it could short/burn out.

If it’s this ludicrous MOST loop system, something to do with optically turning on the amp or channels in the amp. Do my symptoms sound like this? or do they, as I suspect sound more like the amp mother board totally screwing up?
I remember reading about someone unplugging some optical trigger?

5. I think people said it cost about £1,250 just for the amp, any latest good deals?
6. Has anyone found anyone who can repair them?

Any ideas welcome

 

[Submariner1]

Guess what went out to turn off the Comand overnight ...
Gingerly tried the CD.
GUESS WHAT .... PERFECT SOUND ON RADIO, CD, SAT NAV AND PHONE .
The “Sound” parameters all work perfectly ... as if nothing had ever happened!
WTF.
Delighted but ....

As it wasnt the usual wont wake up or dead silence scenario I am hoping its just got its knickers in a twist, or its a low voltage thing.
But maybe I am delusionally trying to convince myself I wont need a new Amp!
However, I really dont understand how everything about the sound could sound so screwed up and then magically repair itself, just by being turned off and left a few hours :-/

Never had an Amp that could lose one side completely , boost and distort the tweeter on the other and have a tiny bit of sound on that side, and let the subs work in a distorted way. :-/

Messing in the car with the dash cams this week and hardly driven any miles have left the battery pretty low.
I recently often find the car after 3 days after a long full charge up, only showing 12.4V or initially until its closed down 12.2V or 12.1V.
Will check tomorrow.

Happy but ...Confused to say the least

 

[Richard Moakes]

Guess what went out to turn off the Comand overnight ...
Gingerly tried the CD.
GUESS WHAT .... PERFECT SOUND ON RADIO, CD, SAT NAV AND PHONE .
The “Sound” parameters all work perfectly ... as if nothing had ever happened!
WTF.
Delighted but ....

As it wasnt the usual wont wake up or dead silence scenario I am hoping its just got its knickers in a twist, or its a low voltage thing.
But maybe I am delusionally trying to convince myself I wont need a new Amp!
However, I really dont understand how everything about the sound could sound so screwed up and then magically repair itself, just by being turned off and left a few hours :-/

Never had an Amp that could lose one side completely , boost and distort the tweeter on the other and have a tiny bit of sound on that side, and let the subs work in a distorted way. :-/

Messing in the car with the dash cams this week and hardly driven any miles have left the battery pretty low.
I recently often find the car after 3 days after a long full charge up, only showing 12.4V or initially until its closed down 12.2V or 12.1V.
Will check tomorrow.

Happy but ...Confused to say the least

Low battery, caused confused DSP in HK amp?

Maybe a full shutdown and amp reboot cleared the issue?

 

[Submariner1]

Low battery, caused confused DSP in HK amp?

Maybe a full shutdown and amp reboot cleared the issue?

Thanks Richard,
I am hoping you are right.
Went out this morning, and immediately checked the battery voltage it read 12.1V ; Then as the modules shut down, over say 2 minutes, this climbed to 12.4V .... not exactly brilliant for a nearly new battery, that was fully charged up last Wednesday!, on a car that has a current drain of only 30mA to 2mA ... which MB say up to 60mA is OK.


I’ve already had one totally buggered new Mercedes Battery last year, and I suspect this one is far from perfect. MB penny pinching downgraded it from 95AH to 92AH, doesnt exactly help us low mileage users either!
Call it coincidence but a 30 mA drain for 4 days is about 3 AHs. So of they had left the spec at 95AH. After 4 days it would probably be at 92AH at 12.7V. (which is where this one starts after a decent charge up, with this replacement battery.).

SO TRIED THE SOUND SYSTEM this morning 3 times on and off ... CRYSTAL CLEAR SOUND ... RADIO, CD, AND SAT NAV, AND THE 7 Logic sound all works perfectly.

I think maybe your idea of a confused DSP might be spot on. Otherwise how can a really scratchy hissy sound and only various bits of the system repair itself.

I just realised in the last few days before this, I noticed my brand new Dashcam failed to start
recording, on one occasion the power light came on and then went off.
Its supposed to come on as soon as the engine starts.

I just wondered if the battery got so low, as the starter kicked in and the volts dropped, did my dash cam, turn itself on and then off. On all three ocaisions pressing the ‘on button’ started the dashcam perfectly and it ran till I stoped the car.

When I got the first dogy new MB battery, it created 5 pages of faults on the star initial test, and some of those were “undervoltage faults” on the Comand system.

 

[Submariner1]

Just as an aside ... thinking I might need a new amp. I looked on eBay
$800 - $900 USD. Interestingly there are 5 superceeded part nos for the amps in my car, most of these were 2 or 3 generations old i.e. all older than my car!
Thats going to end up costing £800 plus landed and taxed in the UK!

As I reckon these failures are a time thing rather than mileage or at least both
Not much point going second hand ... imo
And the condition of them UGH ... may be if they worked and were circa £80 its worth a punt.
Most seemed really rusty!!!
WTF look at this ... blimey looks like it was water damaged!. I certainly wouldnt pay $900 for that ... but then I noticed most of them look like this!

OK I havent yet opened up my left side boot liner, but under the rear center boot liner and boot floor, all the metal parts in mine look pristine! No rust.
Is there a known water leak problem in S Class 221s and CL 500 C216s in the rear wings?
Just puzzled that all these secondhand ones seem rusty.

I Almost dont even want to look at mine :-/

In contrast , Here is a pic of my 2006 DLS Amp 1,000 watts rms Class A, this would annihilate 4 HK amps in volume, grunt and quality. £900 still looks and sounds pristine today.

And thats kept in the boot of an A Class, hmmmm no rust or alloy corrosion there.


I did see one 2010 HK amp for sale .. that looked OKish, but the guy wanted £1,220 ....
IMO much rather buy a new Mercedes one .. at £1,300
Plus if mine went I would really push Mercedes for a contribution, kick up a stink, ref crap build quality.


What do you guys think?

 

[EmilysDad]

I thought you'd connected the lead to your car battery so you can leave your Ctek charger permanently connected to your car?

 

[Richard Moakes]

Well, faced with HK amp failure, I would seriously consider an Audison DMI to extract the sound from the most ring, an Audision BIT 10D for all the crossover and equalisation in the digital domain and finally some JL amps to drive the speakers.

https://www.audison.eu

Or alternatively, there is the MoBridge solution

https://www.mobridge.co.uk/mobridge...ridge-pre-amplifier/da1_digital_pre_amp_most/

 

[Submariner1]

I thought you'd connected the lead to your car battery so you can leave your Ctek charger permanently connected to your car?

Thanks
Yes I have the CTEK traffic light snap on connectors, to make things easy. Plus a circuit breaker to disconnect the Phillips DRLs (so they don’t come on when the voltage exceeds 13.2V)

Technically per WIS the positive should have been connected to that power block under the black control module in front of the battery. But the dealer said it was fine going to the positve battery terminal.

The negative is connected to the proper earth point on the wing arch, as MB said it must go to this not the negative battery terminal or it would screw up the Battery Control Module.


I can then lie the CTEK on the air intake tune and shut the bonnet. But only to the point the bonnet rests on the closed bonnet catches. So its rain proof but not locked.
Sadly she has to live outside till the garage is cleared.

Glad you asked as thats wierd. At 11.00 am the battery looked fairly low at 12.4V and in 4 hours its already got to the “Care” mode at 13.8V .... that seems rather quick for such a weak charger of max. 3.59A and a max of 14.8V.

It seems as though this battery loses charge pretty auickly and also charges up pretty quickly!
Really fed up with this crap battery!
I always found Mercedes batteries to be excellent and far better than generic ones until this last battery swap. I am beginning to think Varta had a batch problem.

I wonder how I could find another MB 95AH AGM battery thats the same size?
Or could I go to 100AH or slightly more.... or would that mess up the Battery control modules.

 

[Richard Moakes]

Complete Audison kit, including amplifier here https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/311558375705

 

[Submariner1]

Well, faced with HK amp failure, I would seriously consider an Audison DMI to extract the sound from the most ring, an Audision BIT 10D for all the crossover and equalisation in the digital domain and finally some JL amps to drive the speakers.

https://www.audison.eu

Or alternatively, there is the MoBridge solution

https://www.mobridge.co.uk/mobridge...ridge-pre-amplifier/da1_digital_pre_amp_most/

I swore I wouldnt do another custom audio upgrade. But if my next car needed a new HK or Burmeister Amp ... at these ludicrius prices I would go that route.
That looks like a seriously sweet option to escape from the MB system and use my DLS amp, and another.

Hopefully you were right and its just a low voltage thing and the amp is fine.

Do you know if I can increase the AHs without having Battery Control Module issues? Say go back to 95AH or slightly more like 100AHs?

 

[alexanderfoti]

Complete Audison kit, including amplifier here https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/311558375705

The Harmon Kardon amp on the 221 is a controller as well, and does other stuff, unlike the other mercs where it just does audio. Its the radio tuner and also processes the PCMCIA data for audio.

 

[alexanderfoti]

I swore I wouldnt do another custom audio upgrade. But if my next car needed a new HK or Burmeister Amp ... at these ludicrius prices I would go that route.
That looks like a seriously sweet option to escape from the MB system and use my DLS amp, and another.

Hopefully you were right and its just a low voltage thing and the amp is fine.

Do you know if I can increase the AHs without having Battery Control Module issues? Say go back to 95AH or slightly more like 100AHs?

Your amp is dead. That is the symptoms of a dead amp. Water typically runs down the hinge and drips straight onto the amp which is why you see so many rusty ones. Water certainly doesn't help their longevity.

Buy new from MB and move on.

Lets not start these battery discussions again please..................

 

[Richard Moakes]

The Harmon Kardon amp on the 221 is a controller as well, and does other stuff, unlike the other mercs where it just does audio. Its the radio tuner and also processes the PCMCIA data for audio.

Got to love MB and their integrated design, that makes anything other than OEM pretty much impossible

 

[alexanderfoti]

Got to love MB and their integrated design, that makes anything other than OEM pretty much impossible

I'm sure it was done intentionally!

 

[Submariner1]

The Harmon Kardon amp on the 221 is a controller as well, and does other stuff, unlike the other mercs where it just does audio. Its the radio tuner and also processes the PCMCIA data for audio.

Thanks
Good to know.
Definitely replace only then.

 

[Submariner1]

Your amp is dead. That is the symptoms of a dead amp. Water typically runs down the hinge and drips straight onto the amp which is why you see so many rusty ones. Water certainly doesn't help their longevity.

Buy new from MB and move on.

Lets not start these battery discussions again please..................

Alex when you say “your amp is dead”
Did you read that the next morning, it worked perfectly. And today it worked perfectly.

(i.e. It failed to work on one small 2 mile journey. And failed to work on the return.
But 4 hours later worked perfectly and has continued to work perfectly for 2 days)

Or are you saying once they show any problem, its just a matter of time before they die for good?
And that they all definitely die?

Do you think an iCarsoft MBII would find a stored amplifier fault code?
Or if not would Star?

I have seen threads by about 3 or 4 people; who had a fault and either it went away or they cleaned it and it worked for a while, but if I am not wrong, sadly they all said it eventuallly died.

Of course by the nature of a forum, where people get help, one gets a distorted view of the bad outcomes ... and I guess many good outcomes never get posted.

So I can monitor it. Should the Cooling fan in the Amp go on the minute you start using it, or is it the type of fan that comes on once it reaches a certain temp.?

 

[alexanderfoti]

Alex when you say “your amp is dead”
Did you read that the next morning, it worked perfectly. And today it worked perfectly.

(i.e. It failed to work on one small 2 mile journey. And failed to work on the return.
But 4 hours later worked perfectly and has continued to work perfectly for 2 days)

Or are you saying once they show any problem, its just a matter of time before they die for good?
And that they all definitely die?

Do you think an iCarsoft MBII would find a stored amplifier fault code?
Or if not would Star?

I have seen threads by about 3 or 4 people; who had a fault and either it went away or they cleaned it and it worked for a while, but if I am not wrong, sadly they all said it eventuallly died.

Of course by the nature of a forum, where people get help, one gets a distorted view of the bad outcomes ... and I guess many good outcomes never get posted.

So I can monitor it. Should the Cooling fan in the Amp go on the minute you start using it, or is it the type of fan that comes on once it reaches a certain temp.?

Yes, its only a matter of time.

 

[Submariner1]

Yes, its only a matter of time.

Thanks Alex,
I thought that was what you meant. Purely because every case I have heard of ends badly.

I found someone who claims to have a 99% success rate.
He said they repair to component level, circa average parts £170. But warned me one of them had severe water damage and needed a whole new motherboard which cost £800 fitted.
Cartronics®
22 High Road BYFLEET SURREY KT14 7QG
Opening hours: Mon-Fri 9am-5:30pm Sat 9am-4:15pm Sun Closed
Obviously I have not used them but info for others who might be interested. As my mother lived about 10 miles away, I think they have been there for many years.
Other costs. As I wouldnt sell the car without disclosing this, if it continues to work perfectly they would charge £79 to open it up and check it out. So I could inform any buyer of the actual status.

He seemed to know all about them, and said mine didnt fit the usual pattern of losing the FM Starions and not waking up. He also said water ran down the boot lid arm and drops right on the amp! Just as you said Alex.

 

[alexanderfoti]

Thanks Alex,
I thought that was what you meant. Purely because every case I have heard of ends badly.

I found someone who claims to have a 99% success rate.
He said they repair to component level, circa average parts £170. But warned me one of them had severe water damage and needed a whole new motherboard which cost £800 fitted.
Cartronics®
22 High Road BYFLEET SURREY KT14 7QG
Opening hours: Mon-Fri 9am-5:30pm Sat 9am-4:15pm Sun Closed
Obviously I have not used them but info for others who might be interested. As my mother lived about 10 miles away, I think they have been there for many years.
Other costs. As I wouldnt sell the car without disclosing this, if it continues to work perfectly they would charge £79 to open it up and check it out. So I could inform any buyer of the actual status.

He seemed to know all about them, and said mine didnt fit the usual pattern of losing the FM Starions and not waking up. He also said water ran down the boot lid arm and drops right on the amp! Just as you said Alex.

Worth a try for £170!!

They start off with crackling on the channels, when they die completely and stop responding on the ring then you loose FM and PCMCIA audio.

Mine did both randomly.

 

[Submariner1]

Worth a try for £170!!

They start off with crackling on the channels, when they die completely and stop responding on the ring then you loose FM and PCMCIA audio.

Mine did both randomly.

Thanks Alex, very useful to know what the symptoms are
Checked it today, all funtioning and sounding perfect.
Possibly the FM channel was a bit slow for the music to start. But that could well be me just being paranoid (and I never listen to the radio).
All stations worked fine.

As its all working perfectly, I will leave it till it breaks, but do my research.

Yeah worth a punt at £170 ...
I might stuff a mini dehumidifier in the boot, as before this, I was putting in the dashcam earth in the rain so it may well be a bit damp in there.