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Model specific boards => Golf mk3 => Topic started by: rehu on 18 November 2009, 13:41

Title: Still having strange sound from HEADUNIT
Post by: rehu on 18 November 2009, 13:41
so im still having this whistling sound from my headunit, which increases when i give some revs.. ive been checking grd cables - all were good.. my amp got like 15 volts(? i think :D) and so i replaced highvoltage sensor.. now its only giving 14.6.. but still that annoying sound, it isnt that big, and comes from headunit! not from mids etc..

ive been thinking should i fit another grd cable from my battery just to make sure it will get enough grding..

you gotta love golfs... tought these arent big problems :D..

anyone have solution for that whistle thing?
Title: Re: Still having strange sound from HEADUNIT
Post by: troublestarter on 18 November 2009, 14:25
whistling will always be either an earthing fault or you have run your rca's/speaker cable next to the amps power cable
have you tried just plugging in another rca into your h/u and just draping it over the seats to the amp
if this solves the problem then you need to re route your rca cable away from the power cable
also check you have a good strong earth usually best to use a seat belt bolt
i have seen lots of installs where the amp is earthed to the tailights and this is a very poor connection option
also make sure your earth is rubbed back to bare metal
Title: Re: Still having strange sound from HEADUNIT
Post by: Alec on 18 November 2009, 14:52
Could that also be something to do with a signal diffuser? I had a mini that used to do it all the time and it was so annoying
Title: Re: Still having strange sound from HEADUNIT
Post by: Len on 18 November 2009, 15:33
My amp is earthed to the tailights and its fine!  :smug:
Title: Re: Still having strange sound from HEADUNIT
Post by: Adam on 18 November 2009, 17:14
My amp is earthed to the tailights and its fine!  :smug:

Until something goes wrong and takes out your rear lights..... :undecided:

Put them on the rear seat belt points is your best bet.
Title: Re: Still having strange sound from HEADUNIT
Post by: andc1 on 18 November 2009, 17:53
earths straight to battery :wink: :wink:
Title: Re: Still having strange sound from HEADUNIT
Post by: rehu on 19 November 2009, 08:23
its might be that rca's are touching the powercable near the amp, have to check that one..  and oh yeah.. i think my speaker cable is going with powercable.. have to fix that one up.. hmm..  my grding is on seatbelt sh!t etc.. so that should be good..
Title: Re: Still having strange sound from HEADUNIT
Post by: Len on 19 November 2009, 11:12
My amp is earthed to the tailights and its fine!  :smug:

Until something goes wrong and takes out your rear lights..... :undecided:

Put them on the rear seat belt points is your best bet.


Well thats how its been for over 4 years so I dont see a problem. An earth is an earth.
Title: Re: Still having strange sound from HEADUNIT
Post by: daytona on 19 November 2009, 23:52
it use to happen yrs ago on older cars.Its interferance from a bad earth,but prob not ye head unit.there is a little box u can buy to cut down on it.go into a maplins or somehwere like that a a headunit place and theyll sell u what u need.
Title: Re: Still having strange sound from HEADUNIT
Post by: Len on 20 November 2009, 10:32
it use to happen yrs ago on older cars.Its interferance from a bad earth,but prob not ye head unit.there is a little box u can buy to cut down on it.go into a maplins or somehwere like that a a headunit place and theyll sell u what u need.


Ummmm this guy is in FINLAND! Dont think Maplins have branches there!  :rolleyes:
Title: Re: Still having strange sound from HEADUNIT
Post by: daytona on 20 November 2009, 13:09
maybe not u never know :smiley: but he gets m :shocked:y drift
Title: Re: Still having strange sound from HEADUNIT
Post by: troublestarter on 20 November 2009, 18:45
the problem with earthing to a taillight is that the metal is very thin and think about what the actual thread of the light is held on by plastic (not a good conductor of electricity) and a very tiny amount of the thread contacts with the very thin piece of metal it is passing through
so you are relying on the bolt to create the earth which is not ideal
also connecting the earth directly to the battery in itself sounds a good idea however this can cause interference problems in itself in that it is more succeptible to alternator interference
move the speaker cables away from the power cable that will help
the little box you can buy is actually called a ground loop isolator and invariably these do not work
they plug in line on the rca coming from the h/u and do not actually eliminate the noise but effectively reduce it but as i said most of the time the do not work
Title: Re: Still having strange sound from HEADUNIT
Post by: Adam on 20 November 2009, 18:48
Is it a Pioneer Headunit? The ground fuse in the HU for the RCAs blow causing a whine.

I had it, I grounded the RCAs like this -
(http://www.team-bhp.com/forum/iipcache/76310.jpg)
Title: Re: Still having strange sound from HEADUNIT
Post by: troublestarter on 20 November 2009, 19:12
Is it a Pioneer Headunit? The ground fuse in the HU for the RCAs blow causing a whine.

I had it, I grounded the RCAs like this -
(http://www.team-bhp.com/forum/iipcache/76310.jpg)
this is very common with pioneers
Title: Re: Still having strange sound from HEADUNIT
Post by: rehu on 20 November 2009, 21:30
its kenwood, havent still found the problem..
Title: Re: Still having strange sound from HEADUNIT
Post by: rehu on 25 November 2009, 20:33
i placed grd on the backseat beltpoint now and still having this problem, i even placed rca's better etc.. everything now should be good.. strange.. maybe something on kenwood then..
Title: Re: Still having strange sound from HEADUNIT
Post by: kells on 25 November 2009, 21:24
best plac eis on the boot floor under spare wheel, drill small hole and fit earth cable with a self tapping screw, make sure you grind off any paint so it makes contact..


oh and bin the kenwood buy a ALPINE   :cool:
Title: Re: Still having strange sound from HEADUNIT
Post by: Adam on 25 November 2009, 21:32
oh and bin the kenwood buy a ALPINE   :cool:

YES listen to the man
Title: Re: Still having strange sound from HEADUNIT
Post by: rehu on 26 November 2009, 06:05
yeah i will throw away kenwood what i just bought with 200 euros?
sounds like a plan man..

it isnt about the earthing at amp, im 100% sure about that.. its something about either batterys grounding.. or headunits grounding is crappy..