Submariner1
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- Your Mercedes
- CL500 2009 5.5
Oh well the intermittant distortion played up again today.
This time it sounded like the tweeter and also the mid range was distorting. In fairness maybe I just heard the tweeter before.
[ Checking the wiring diagram, the tweeter spurs off the Mid Range driver ... so that is indicative that either that channel is suspect, or their could be an issue with the voice coil or wiring to either or both speakers. ... thats a pig as it means the whole door card has to come off
]
Anyway ... So time to remove the amp!
Seriously tight top speaker and power connectors :-/
Result
Some good news ....
The fan cover spyder grill, that in the car, possibly looked a little Aluminium corroded, turned out to be just deep black dust.
TBH it looked like brake dust!
So thats encouraging as it does not look water damaged. IMO.
Similar mucky stuff inside, directly under the fan! Pretty much around the yellow circled area.
I did trial wipe it off with a ear bud soaked in IPA, it came off very easily
see red circled area.
It came off so easily, I reckon the right spray cleaner, like Servisol or Deoxit5 should clean it totally.
I would be interested to hear from anyone else who has had HK Logic 7 Amplifier failures, and who opened up their amps like Simon or Alex or Dave or Ray etc.
Q. Was your PCB :-
1. dirtier, or cleaner or the same etc.
2. Did it look like the same deep black dust ? Looks just like brake pad dust.
3. Or did yours show any signs of water corrosion or heat burn.
I am hoping that maybe this dust is conductive, and that BBA might be able to sort it out.
Is brake pad dust conductive?
I was going to take the back off, but I wanted to know can one turn it upside down with the fan cover attached, and just undo the 7x little Torx T8 set screws. Or does one have to support the motherboard when you do this?
I did take off the Tweeter speaker pod, but couldn't pull the tweeter wire plug out!! It moved a mil or so back and forth but just would not come out :-/
I mean I really pulled.
Looking at the replacement plug, I bought one just in case, plus I know what the connector is like to undo it , there only seems to be a tiny sprung plastic catch.
See red arrow, as the tab marked in yellow locks in the wires
Any ideas to get this off
I am no expert ... but imo it doesnt look water damaged, and possibly its just an Amplifier electronics issue.
So thats good news as the USA Becker repair centre said you really cant repair the water damaged ones.
Oh well time to find a decent container to ship it off in
Bye bye £175
This time it sounded like the tweeter and also the mid range was distorting. In fairness maybe I just heard the tweeter before.
[ Checking the wiring diagram, the tweeter spurs off the Mid Range driver ... so that is indicative that either that channel is suspect, or their could be an issue with the voice coil or wiring to either or both speakers. ... thats a pig as it means the whole door card has to come off
Anyway ... So time to remove the amp!
Seriously tight top speaker and power connectors :-/
Result

Some good news ....
The fan cover spyder grill, that in the car, possibly looked a little Aluminium corroded, turned out to be just deep black dust.
TBH it looked like brake dust!
So thats encouraging as it does not look water damaged. IMO.

Similar mucky stuff inside, directly under the fan! Pretty much around the yellow circled area.
I did trial wipe it off with a ear bud soaked in IPA, it came off very easily
It came off so easily, I reckon the right spray cleaner, like Servisol or Deoxit5 should clean it totally.
I would be interested to hear from anyone else who has had HK Logic 7 Amplifier failures, and who opened up their amps like Simon or Alex or Dave or Ray etc.
Q. Was your PCB :-
1. dirtier, or cleaner or the same etc.
2. Did it look like the same deep black dust ? Looks just like brake pad dust.
3. Or did yours show any signs of water corrosion or heat burn.
I am hoping that maybe this dust is conductive, and that BBA might be able to sort it out.
Is brake pad dust conductive?
I was going to take the back off, but I wanted to know can one turn it upside down with the fan cover attached, and just undo the 7x little Torx T8 set screws. Or does one have to support the motherboard when you do this?

I did take off the Tweeter speaker pod, but couldn't pull the tweeter wire plug out!! It moved a mil or so back and forth but just would not come out :-/

I mean I really pulled.
Looking at the replacement plug, I bought one just in case, plus I know what the connector is like to undo it , there only seems to be a tiny sprung plastic catch.
See red arrow, as the tab marked in yellow locks in the wires
Any ideas to get this off

I am no expert ... but imo it doesnt look water damaged, and possibly its just an Amplifier electronics issue.
So thats good news as the USA Becker repair centre said you really cant repair the water damaged ones.
Oh well time to find a decent container to ship it off in
Bye bye £175
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