Fixing Water Damaged HK Wiring

[Restyle]

The Problem
Ive had a particular problem with my Aug 2004 build HK Amp unit for a couple of years now.
The problem started off with whole radio / amp unit occasionaly loosing power - the display vanishing for a few seconds.
The problem got gradually worse happening more often, until the unit completely lost all power.
An inspection inside both the amp & head unit showed no obvious faults - but on inspecting the head units connectors, I found the supply voltage was variable & when measurable was only around 3 volts.
From what I could figure, the wiring wasn't straightforward as the amp seemed to supply the HU with this power, but it had dissappeared somewhere along the way.
I had also tried swapping both the Amp & HU but the problem remained

The Temporary Fix
As a quick bodge / workaround, I simply fed the missing permanent supply with the feed from the ignition switched supply.
I had to also incorporate a switch into this circuit to switch off this feed when the ignition was off, as I found it could confuse rear wiper & alarm into coming on in some circumstances - But it worked.

The Permanent Fix
Earlier Today, I had been been looking around under the drivers footwell carpet for the 'Diode' that connects to the high level brake light - When It fails, the high level light remains permanently on even with the ignition off.
Although I didn't locate the Diode, I did find what seems to have caused the HK amp & HU to loose power.
Just in front of the seat lying next to the wiring loom was a very badly corroded 4- way connector.
I`ll add that the footwell area was also awash with water from an as-yet unidentified leak.
The connector comprised of 4 Red/Brown cables joined in a clear plastic sheath.
As can be seen from the pictures, it was so badly corroded that the cables fell apart when touched & the 'clear' sheath was now green with copper corrosion.
I had to cut the ends back a few inches in order to find some decent copper, but when I rejoined them with a single 'choc block' connector - the radio immediately came into life - bypassing the 'quick fix' isolating switch I had previously installed.

Hope this helps someone with similar problems with their HK amp.

[davecrook1]

Good write up.. My stereo has got massive interference over the music, then the sound stops altogether and I haven't a clue why? Is it the HU or amp?

[Restyle]

Quote: Originally Posted by davecrook1 (original)

Good write up.. My stereo has got massive interference over the music, then the sound stops altogether and I haven't a clue why? Is it the HU or amp?

I'm by no means any expert on the HU or Amp, however a few more details about how it fails might help to narrow down the possible cause.
So :-
1/ What type of 'Interference' is it exactly - ie ... A crackling - A whining - Volume Decrease - White Noise - Other ?

2/ Is it the same Interference on both CD & Radio ?

3/ Do you have a multi CD changer ?

4/ Is it the same whether the engine is running or not - or does it vary with engine speed ?

5/ Does going over bumps make it worse or trigger it off ?

6/ When the sound stops altogether, does the display on the HU remain unchanged as it was - or maybe flicker - or totally dissappear ?

7/ After it stops altogether - how long is it before it comes back on again - or do you have to switch ignition off & on again to 'reset' it ?

8/ What model & build date is your car ?

[davecrook1]

Interference is like a really badly tuned radio station.. It does it when it's on radio or cd.. I've got no cd changer just the hk setup... The noise doesn't change whether it be smooth or rough.. Now its stopped altogether but occasionally comes on once the cars been turned off but then goes off after 5 seconds or so.. The HU doesn't change just stays on a displays as usual.. Although I have noticed that when the sound disappears so does the HK options on the HU..
The car is an 03 plate cooper s

[Restyle]

Its sounding like it could be the HK amp unit.
Easy option is to take it apart & check the board out for obvious dry joints on any of the plug connections on the pcb - other than that it gets expensive with an exchange amp costing a couple of hundred

[davecrook1]

I did take it off but mine seems to be missing the spider.. Maybe this is the prob .. The amp looked ok but nothing worked after I'd took it apart and plugged it back in.. Guess another amp is on the cards

[drozd]

Quote: Originally Posted by Restyle (original)

Its sounding like it could be the HK amp unit.
Easy option is to take it apart & check the board out for obvious dry joints on any of the plug connections on the pcb - other than that it gets expensive with an exchange amp costing a couple of hundred

Where are exchange amps avalible from?

[Restyle]

Quote: Originally Posted by drozd (original)

Where are exchange amps avalible from?

As well as seeing them crop up on ebay, you can get them from various MINI breakers/repairers around the country.
My local MINI Breaker is MINIMatt at Shifnal Shropshire >> MiniMatt|BMW|MINI|Modifications|Parts|Spares|Servi ce|Tuning|Repairs|Racing
(who kindly let me try out different head units when I was trying to find the cause of my HK fault}

[drozd]

Quote: Originally Posted by Restyle (original)

As well as seeing them crop up on ebay, you can get them from various MINI breakers/repairers around the country.
My local MINI Breaker is MINIMatt at Shifnal Shropshire >> MiniMatt|BMW|MINI|Modifications|Parts|Spares|Servi ce|Tuning|Repairs|Racing
(who kindly let me try out different head units when I was trying to find the cause of my HK fault}

OK I know second hand ones crop up, but an exchange amp indicated someone was selling reconditioned ones.

[Restyle]

Quote: Originally Posted by drozd (original)

OK I know second hand ones crop up, but an exchange amp indicated someone was selling reconditioned ones.

I was under the impression that exchange HK amps were available - but seems Im wrong

[drozd]

Quote: Originally Posted by Restyle (original)

I was under the impression that exchange HK amps were available - but seems Im wrong

Its a shame as I need one, my front Midrange speakers are not working but the speakers themselves are ok,